Method for producing attrition-resistant catalyst binders

ABSTRACT

Attrition-resistant binders can be prepared by a process wherein a slurry of clay particles is brought to either a low pH level (e.g., 1.0 to 3.0) or to a high pH level (e.g., 14.0 to 10.0) and mixed with a phosphate-containing compound in a concentration of from about 2.0 to about 20.0 weight percent. Preferably, the resulting slurry is spray dried and the particulate products of the spray drying are then calcined to produce attrition-resistant binder particles.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is generally concerned with the production ofattrition-resistant binder formulations such as those used to bindcatalyst particles into those forms (e.g., microspheroids) which arecommonly employed in fluid catalytic cracking processes. Moreparticularly, this invention is concerned with the use of certaininexpensive, naturally occurring clay materials, e.g., kaolinites--inplace of certain more expensive, synthetic materials, e.g., syntheticsilica and/or alumina materials--as principle ingredients in such binderformulations.

2. Description of the Prior Art

Clays have been used in catalyst matrix systems for many years. Forexample, one very important development in petroleum "cracking" was thecatalytic decomposition of gas oil in the presence of certain naturallyoccurring clays such as kaolinites in an atmosphere of the gas oil's ownvapor. However, the use of such clays as catalysts per se has diminishedover the years. There were several reasons for this. One of the mostimportant of these reasons was the fact that most naturally occurringclays lack the quality of "attrition-resistance" which is very importantin any catalytic system which places its catalyst particles in "fluidmotion." Moreover, catalytic clays of this type also have to beextensively treated before they can be used as "cracking catalysts." Forexample U.S. Pat. No. 2,848,423 notes that in order for its particularprocess to be effective, its kaolin catalyst ingredient first has to be"sized" in order to obtain kaolin particles of less than about 2microns. These sized particles are then aggregated and subjected toelevated temperatures. The resulting materials are thereafter treatedwith hydrogen sulfide at about 1200° F. in order to form aggregateswhich, in turn, are exposed to ammonium chloride in order to selectivelyremove any iron present in the kaolin aggregates.

The need for so many preparatory steps, in conjunction with the factthat catalyst particles having high kaolin concentrations are subject tounacceptable attrition losses, provided a great deal of motivation tofind more suitable catalyst materials. Eventually a large variety ofother amorphous catalytic materials, and especially those having largeproportions of alumina, were developed. The use of these materialsrepresented a very significant step in this art because not only werethese other alumina-containing materials more catalytically active thankaolin clays, they also were generally much more attrition-resistant.Later it was found that certain naturally occurring, crystalline zeolitematerials such as y-faujasites also made very effective catalysts. Theytoo proved to be generally more attrition-resistant than naturallyoccurring clays. However, because of their small crystalline sizes,naturally occurring zeolite particles have to be bound together with anattrition-resistant binder system in order to render them suitable foruse in fluid catalytic cracking units (FCC units). Still later, wholeclasses of very effective synthetic, crystalline, zeolite catalysts,e.g., ZSM-5 were developed. Here again, since these synthetic zeolitesalso have very small crystalline sizes (e.g., average diameters of lessthan about 5 microns), they too have to be bound together in largerparticle units by various "binder" or "glue" formulations. Those made ofsilica, alumina, silica/alumina, silica/magnesia, etc. are commonlyemployed for such purposes.

It also should be noted that not only do many of these glue or bindermaterials serve as attrition-resistant binder matrices, they also oftenserve as catalysts in their own right. This independent catalyticactivity has proved to be an advantage in catalyzing some chemicalreactions, but a disadvantage in catalyzing many others. Moreover, manyof these glue or binder materials also are chemically reactive with manyof the different kinds of catalyst particles they are called upon tobind together. Such chemical reactivity between a given binder materialand a given species of catalyst particle may be an advantage in somecases, but generally speaking it is not considered to be an advantage;and in many cases it may well constitute a serious detriment to thecatalytic activity of a given species of catalyst.

Those familiar with this art also will appreciate that most binderformulations can be used in at least five different ways, e.g., (1) theycan be used to "glue together" (hence their appellation "binder"materials) various catalyst particles into larger catalyst matrices,especially in those cases where the catalyst particles are so small thatthey would be susceptible to unacceptable elutriation losses, (2) theycan be used to grow, in situ, certain lattice structures useful informing catalyst matrices, (3) they can be impregnated with liquidcatalyst solutions such as those of various Group VIII metals, (4) theycan be introduced as catalytically inert binder particles into variouschemical processes in order to "dilute" the concentration of, and hencethe activity levels of, active catalyst particles being used in saidprocesses and (5) they can be used as catalytically active materials intheir own right; that is to say they can simultaneously serve both as a"binder" and as a "catalyst".

The need to perform so many varied catalytic functions also has resultedin an ever expanding need for catalyst materials of greater and greatercomplexities. Because of this, catalyst particles having more than onespecies of active catalyst are often employed to simultaneously carryout several different catalytic duties. For example, use of severaldifferent kinds of zeolite catalysts, e.g., the use of zeolite catalystsand amorphous catalysts, in the very same particle has proven to be aneffective technique in such varied chemical processes as hydrocracking,alkylation, dealkylation, transalkylation, isomerization andpolymerization. Many low-soda exchanged Y-zeolite catalysts andultra-stable Y-zeolite catalysts also are known to be especially usefulwhen agglomerated into multi-catalyst-containing particles.

The use of such multi-component catalysts also has led to a need formore and more "universally non-reactive" binder materials. That is tosay that the need for more complex catalyst particles has intensifiedthe need for binder materials which are capable of binding several kindsof catalyst particles into suitable forms (e.g., into microspheroidalparticles) without the binder either entering into undesired chemicalreactions with any of the different catalyst species in a given particleor without the binder entering into the catalytic reaction(s) beingcatalyzed by that particle. At present, various complexes of alumina,alumino-silicate compounds, silica, magnesia, silica-magnesia, chromia,zirconia, gallium, germanium, etc., are the materials most widelyemployed as "universal" binders. For the purposes of this patentdisclosure, all such universal binder materials may be thought of asbeing--and referred to as--"glue" or "binder" materials. That is to saythat--if they are not to be used in their own right as catalyticmaterials--their chief function is to "glue" various active catalystparticles together to form larger particles. However, as was previouslynoted, many of these universal binder materials are in factcatalytically active in certain catalytic environments where it would bemore advantageous if they were completely inert.

Those skilled in this art also will appreciate that regardless of thespecific catalytic duties to which a given binder material is put in agiven fluid catalytic process, elutriation losses will occur whenparticles of different sizes, shapes and/or velocities undergointer-particle impacts. Such impacts tend to shatter or otherwise damagethe matrices of all such materials. Hence, smaller and smaller fragmentsare constantly being formed and subsequently lost via cycloneelutriation of the resulting smaller particles. Fragments havingdiameters of less than about 20 microns are especially susceptible toelutriation losses.

Other losses occur as a result of differences in the densities of two ormore catalyst species used in the same "fluid" process. That is to saythat in many modern catalytic cracking processes, it is not at alluncommon to have as many as a half dozen different kinds of catalystspecies simultaneously circulating through a reaction system in order tocarry out distinctly different catalytic functions. Consequently,classification and sequestration are often caused by the action of amass of reaction vapors sweeping through and separating different kindsof catalyst particles according to their density differences.Consequently, use of the very same binder material to make differentcatalyst species is a widely employed practice since it tends to createlike densities in the different particle species. Thus, for all of theabove noted reasons, the catalyst-employing chemical arts have anongoing interest in developing more attrition-resistant, "universal",binder formulations.

The catalytic arts also have long recognized that certain naturallyoccurring clays have those "universal" binding qualities which are souseful in formulating a wide variety of catalysts. However, prior artattempts to use such clays in catalyst formulations have been thwartedtime and again by the fact that those binder materials having largeproportions of such clays are usually much too "soft" for use in fluidcatalytic systems. That is to say that most high clay content binder orcatalyst materials generally lack the quality of "toughness" or"attrition-resistance"; and, hence, easily succumb to those forcesassociated with particle impacts which eventually lead to the creationof smaller particles and unacceptable elutriation losses. Consequently,the role of naturally occurring clays in the catalytic arts has steadilydecreased since the 1930's when they were widely used as petroleumcracking catalysts. At present, naturally occurring clays such as kaolinare used sparingly as catalysts or as binder materials, and then only inconjunction with much larger proportions of those alumina,silica-alumina, silica-magnesia, zeolite, etc., "glue" type materialspreviously noted.

Naturally occurring clays do, however, continue to play somewhat largerroles in some catalyst formulations as "filler" ingredients. In this"filler" capacity, such clays (in conjunction with various inorganicglues of the types previously described) are used in order to give"body" to certain catalyst matrices at the lowest possible costs.Perhaps the most important property of a clay for fulfilling such a"filler" function is that it be chemically inert with respect to thecatalytic ingredients employed in a given formulation. As was previouslynoted, this same characteristic also is useful when a clay is used as a"binder" material. However, the role of a clay "filler" is not exactlythe same as that of a clay "binder" in the herein described processes.For example, a clay "filler", most preferably, will not enter intochemical reactions with any of the other ingredients in the binderformulation. On the other hand, when acting as a "binder", a clayingredient, most preferably, will react to some limited degree with someother ingredient in the binder formulation. As will be seen in laterparts of this patent disclosure, applicant's clay ingredient chemicallyreacts with a phosphate-containing ingredient to form a viscous reactionproduct. This reaction product, once formed, should not, however,chemically react with any catalyst particles which are subsequentlyintroduced into the formulation.

It also should be emphasized that in these filler applications, certainclays may comprise high percentages (e.g., higher than about 10 percentby weight) of the overall catalyst formulation; but, again, in suchcases, they act as completely inert "fillers" and not as either "activecatalysts" or as "binder materials". Those skilled in this art also willappreciate that filler clays also should have certain particle sizesand/or morphologies. Typically, certain inert kaolin clay materialshaving particle sizes less than about 0.25 microns are employed for usein such "filler" capacities. Moreover, the use of so-called "ball" clays(as opposed to "plate" or "rod" forms) is a highly desired--andsometimes mandatory--attribute of those filler clay particles used inproportions larger than about 10 percent. Absence of these qualitiesnormally will detract from the attrition-resistance of any particles inwhich clays serve as fillers. On the other hand, clays used in binderroles generally do not have as stringent size and morphologyrestrictions.

The fact remains, however, that since naturally occurring clays are somuch less costly than the alumina, silica, etc. "glue" materialspreviously noted, and since they can bind so many different kinds ofcatalyst particles without chemically reacting with them, and since theyare catalytically inert with respect to so many chemical reactions,binder formulations having large clay proportions would be very welcomeadditions to the catalyst-employing arts--if the attrition problemscurrently associated with their use as binders (as opposed to their useas fillers) could somehow be obviated.

It also should be noted that binder and/or catalyst matrix attritionproblems arising from the presence of large proportions of such clayshave been addressed through the use of greater proportions of "hard"binder and/or catalyst ingredients (and especially through the use ofgreater proportions of hardness-imparting "glue" or catalystingredients). That is to say that, in the past, attrition-resistanceproblems with clay-containing catalyst particles have been addressed byusing relatively less clay and relatively more hardness impartingingredients such as alumina and/or silica. Attrition-resistance problemsalso have been addressed--incidentally--through the use of variouschemical treatments which are primarily employed to implement, improveor diminish the catalytic activities of various active catalystmaterials. By way of example only, U.S. Pat. No. 4,594,332 recognizessuch activity/hardness interrelationships in that it teaches productionof hard, fracture-resistant binder systems from zeolites of the pentasilfamily by use of a process wherein water, organic additives such ashydroxyethylcellulose and a silicate are added to zeolite particles sothat the resulting particles are rendered both more catalytically activeand more attrition-resistant. However, this favorable outcome is not theusual case; indeed, very often catalytic activity must be "sacrificed"in direct proportion to any gains made in attrition resistance.

Another set of problems associated with production ofattrition-resistant catalyst particles follows from certain inherentrestrictions which must be placed upon those so-called "gel reaction"processes which are commonly employed to make many kinds of catalysts.For one thing, they must be carried out in some rather restricted pHranges (especially those confined to alkaline, i.e., 8.0 to 14.0 regionsof the pH scale). For example, the gel reaction step of U.S. Pat. No.4,471,070 (the 070 patent) is restricted to a 8.5 to 10.5 pH range.Similarly, the gel reaction taught by U.S. Pat. No. 4,728,635 (the 635patent) is preferably carried out in a 7.0 to 10.5 pH range.

The rather narrow, alkaline, pH limitation placed upon the processtaught by the 070 patent follows from the fact that higher pH valueswould force a chemical shift which favors the formation of alkalinealuminum, i.e., the aluminate anion, AlO₂.sup.Θ. However, aluminateanions are soluble in water and therefore subject to being "washed out"during subsequent filtration steps to which these materials must besubmitted. Similarly, the 635 patent teaches use of aluminum oxide in analkaline medium of magnesium compounds in order to attain a distinctlyalkaline ionization medium. Under such conditions, small dispersedparticles of aluminum oxide having maximum effective surface areas arerapidly associated with water molecules and thereby establish anequilibrium which also favors the anionic form of aluminum as itsaluminate (i.e., AlO.sup.Θ₂) ion. Many other gel reactions have similarrestrictions to the use of mildly alkaline reaction systems. Indeed, theprior art has, to a large degree, accepted the idea that any attempts tocarry out gel reactions in either a strongly basic or a strongly acidicreaction system will usually lead to some degree of damage toaluminum-containing molecules which tends to weaken any catalyst matrixmade from them.

This restriction of the prior art to mildly alkaline reaction conditionshas several implications which bear upon the novelty and scope ofapplicant's invention because the chemical reactions of the hereindescribed processes can be--and in many instances preferablyare--carried out in strongly acidic conditions as well as in stronglyalkaline ones. This fact indicates that applicant's reactions arequalitatively different from the "gel reactions" employed by the priorart. Thus, applicant's processes can be distinguished from much of theprior art by the fact that they have both "acid versions" and "alkalineversions". Regardless of the version employed, however, the mostimportant aspect of applicant's processes remains the fact that they canemploy large proportions of naturally occurring clays in order toproduce binder matrices (and binder/catalyst matrices) without therebyrendering those matrices too "soft" for use in fluid catalyticprocesses. The fact that extremely high levels of attrition-resistancecan be achieved without "sacrificing" the catalytic activity of anyactive catalyst particles which may be placed in applicant's bindersystems also is a most important aspect of these processes.

SUMMARY OF THE INVENTION

This invention generally involves the use of: (i) large proportions(i.e., proportions greater than about 20%, and in many cases proportionsup to about 98%) of naturally occurring clays (e.g., kaolinites), (ii)various phosphate-containing compounds, (iii) select pH conditions and(iv) certain drying and calcination procedures in order to producehighly attrition-resistant binder formulations. That is to say that theattrition-resistant qualities produced by the hereinafter describedprocesses are the result of both chemical reactions and physical process(such as the use of heat) to produce binder materials which, among otherthings, have certain vitreous or glass-like qualities which render theparticles attrition-resistant. Consequently, a large part of this patentdisclosure will be devoted to describing the chemical parameters of aseries of clay/phosphate reactions in conjunction with those temperatureparameters which must be placed upon the products of those chemicalreactions in order to impart the desired vitreous qualities to the endproducts of these reactions and procedures.

Another insight into applicant's overall invention can be obtainedthrough the understanding that the herein described processes can becarried out from either of two different initial pH orientations. Onemight be thought of as applicant's "acid reaction" orientation; theother might be regarded as an "alkaline reaction" orientation. In eithercase, however, the binder materials ultimately produced by applicant'sprocesses can be used in their own right; or they can be used to bind awide variety of small, catalytically active, particles into more usefulforms such as those microspheroidal catalyst "particles" which arecommonly employed in fluid catalytic cracking operations.

Another insight into this invention can be gained from an appreciationthat both the acid versions and the alkaline versions of applicant'sprocess can, in turn, be carried out to produce particles falling intotwo broad categories. One category might be termed: "simple binderparticles" (wherein the word "simple" implies those binder particleswhich do not contain active catalyst ingredients); the other categorymight be termed: "catalyst-containing binder particles" (i.e., particleswhich do contain active catalyst particles). The simple binder particlesand the catalyst-containing binder particles can each be broken downinto two further subcategories, i.e., those whose principle ingredientsare clay and phosphate and those whose principle ingredients are clayand an "auxiliary binder component" which, in turn, is comprised of oneor more auxiliary binder material(s) of the "glue" type binderspreviously noted (e.g., alumina, silica, silica-alumina,silica-magnesia, etc.) and one or more phosphate-providing compound(s).Applicant's catalyst-containing binder particles can likewise employeither of these two kinds of binder systems.

Generally speaking the "simple binder particles", (i.e., thosecontaining only clay and phosphate ingredients) will contain from about80 to about 98 percent clay and from about 2 to about 20 percentphosphate. Phosphate percentages of from about 6 to about 12 weightpercent are even more preferred in these simple binder particles. Anysimple binder particles which contain less than about 2.0 percentphosphate will, however, generally require the presence of an auxiliarybinder component. When such auxiliary binder components are used, thephosphate component proportion can vary from as low as about 0.25percent to as high as about 20 percent. Proportions from about 0.25 toabout 2.0 percent phosphate are, however, highly preferred when suchauxiliary binder components are employed, if for no other reason thanthe relative costs of the alternative ingredients. Broadly speaking, theauxiliary binder component will comprise from about 5.25% to about 60.0%of the resulting binder particles. That is to say that the resultingsimple binder particle having an auxiliary binder component will becomprised of from about 40 to about 94.75 percent clay and from about5.25 to about 60 percent of the auxiliary binder component. Theauxiliary binder component, in turn, will be comprised of from about 5.0to about 40 weight percent of an auxiliary binder material of the typespreviously mentioned (alumina, silica, magnesia, etc.) and from about0.25 to about 20 percent phosphate. In other words, the auxiliary bindercomponent will be comprised of an auxiliary binder material (i.e., a"glue" type binder other than the clay ingredient of the given binderformulation) and a phosphate-providing compound such as phosphoric acid,ammonium phosphate, etc. The resulting end product particles can becomprised of virtually any proportions of the phosphate-providingcompound and the auxiliary binder material (e.g., alumina, silica,silica-alumina, etc). However, the phosphate-containing material of theauxiliary binder component must be sufficient to provide the end productbinder particles with at least about 0.25 percent phosphate. That is tosay that, the auxiliary binder component might provide from about 0.25to about 20.00 weight percent phosphate to the end product binderparticle, but will most preferably provide from about 0.25 to about 2.0percent phosphate. In any case, one or more auxiliary binder materialswill comprise the remainder of the auxiliary binder component. In otherwords, the auxiliary binder material (e.g., alumina, silica,silica-alumina, etc.) may comprise from about 5.0 to about 40.0 weightpercent of the end product binder particles. Within these proportions,those auxiliary binder components which provide the end product binderparticles with from about 1.0-2.0 weight percent phosphate and fromabout 5.0 to about 20.0 weight percent of the auxiliary "glue" or bindermaterials (e.g., alumina, silica, alumina-silica, etc.) are mostpreferred. As in the previous case involving the use of binders made ofonly clay and phosphate, the remainder of the auxiliary bindercomponent-containing end product matrices will be comprised of a claycomponent which will represent from about 40 percent to about 94.75percent of said end product matrices.

The "catalyst-containing binder particles" of this patent disclosurealso can be of two general types, i.e., (1) those having a clay andphosphate binder system in which the active catalyst component "resides"and (2) those having an auxiliary binder component and a clay componentwhich together constitute a binder system in which an active catalystcomponent "resides." Some particularly preferred versions of theparticles resulting from these clay/phosphate/catalyst embodiments ofapplicant's invention will generally be comprised of from about 20 toabout 95 percent clay, from about 2.0 to about 20 percent phosphate andfrom about 3 to about 60 percent active catalyst. That is to say thatthese particular versions of applicant's processes employ only clay,phosphate and catalyst. However, other embodiments of applicant'scatalyst-containing matrices (a la the simple binder formulations notedabove) can employ applicant's "auxiliary binder components" rather thanclay/phosphate binder formulations comprised of only clay and phosphateingredients.

Those "catalyst-containing binder particles" prepared with an auxiliarybinder component (rather than phosphate-containing compounds alone)generally will have an overall constitution somewhat analogous to those"simple binder particles" which employ applicant's "auxiliary bindercomponent" rather than only a phosphate-containing compound. Forexample, the auxiliary binder component in such catalyst-containingbinder particles also will constitute from about 5.25 to about 40 weightpercent of the resulting catalyst particles. The remainder of the endproduct catalyst particles will be comprised of a clay component (whichwill comprise from about 20 to about 91.75 weight percent of theparticle) and a catalyst component which will preferably comprise fromabout 3.0 to about 40.0 weight percent of the resultingclay/phosphate/auxiliary binder catalyst particles.

As was the case of the "simple binder particles", the auxiliary bindercomponent of these "catalyst-containing particles" can accommodatevirtually any proportions of a auxiliary binder material and phosphate,but they too are limited by the caveat that the phosphate must bepresent in an amount sufficient to give the resulting catalyst particlesa phosphate content of at least about 0.25 percent by weight. Auxiliarybinder material proportions of from about 5 to about 20 percent arehighly preferred in the resulting particles. The phosphate percentage ofthese end product catalyst particles can likewise range from about 0.25to about 20.0 weight percent of the end product; but here again,phosphate percentages of from about 0.25 to about 2.0 are preferred (iffor no other reason than the relative costs of the alternativeingredients) in these auxiliary binder-containing formulations. And,once again, auxiliary binder component material(s) such as alumina,silica, alumina-silica, etc.) are preferred ingredients for making upthe remainder of these auxiliary binder components. The auxiliary bindermaterials will preferably range from about 5.0 to about 20.0 percent ofthe end product catalyst particle. Again, those auxiliary bindercomponents which provide these auxiliary binder/catalyst-containing endproduct particles with from about 0.25 to 2.0 percent phosphate--andfrom about 5-20 weight percent of the auxiliary binder material(alumina, silica, silica-magnesia, alumina-magnesia, etc.) are highlypreferred.

As a final note on the subject of the relative proportions of theseingredients, it should also be understood that, unless otherwiseindicated, the percentage compositions associated with theabove-described binder or catalyst particles--as well as the ingredientsfrom which they are made--should be taken to mean percentages by weightand not by volume. It also might be noted at this point that, for thepurposes of this patent disclosure, the term "particles" should bebroadly construed to include sizes larger than the 60-80 micron sizesusually imparted to those microspheroidal catalyst particles which areused in fluid catalytic cracking units. Indeed, for applicant'spurposes, the term "particles" also should be taken to include thosecatalyst "extrudates" which are commonly made in much larger sizes (0.5to 1.0 inches) through the use of so-called catalyst "extrusion"techniques. Such "larger" particles are often employed in "stationary"catalyst beds rather than in "fluid" processes.

Now, having noted various possibilities with respect to the identitiesand relative proportions of the ingredients, it next should be verystrongly emphasized that applicant's overall inventive concept does notreside solely in the use of those ingredients and/or their relativeproportions. Utilization of the hereinafter described pH and calciningconditions also are extremely important to the overall success of eachversion of applicant's processes.

In order to gain an initial appreciation for the importance ofapplicant's pH-providing steps, it again should be noted thatapplicant's overall invention has "acid reaction" versions and "alkalinereaction" versions. Either of these versions can be employed toinitially place a clay under an "extreme" pH condition before said clayis chemically reacted with an appropriate phosphate ingredient. Forexample, in most cases applicant has found that if a clay slurry is notfirst adjusted to an appropriate pH level, e.g., first brought to astrongly acidic pH (a pH of from about 1.0-3.0) or in some cases firstbrought to a strongly basic pH level (e.g., a pH of from about13.0-10.0), before the phosphate-containing compound is introduced intothe slurry, then the desired attrition-resistance qualities in anyresulting matrix particles will be greatly diminished.

Poor results with respect to the "catalytic activity" (as opposed to"attrition-resistance") of the resulting particles also will generallyresult from introducing any catalyst into the clay/phosphate slurrybefore the slurry is brought to a pH of from about 4.0 to about 8.0.That is to say that if the catalyst particles were introduced into aslurry while it is in the strong acid pH range of from about 1.0 toabout 3.0 range (or while it was in a strong alkaline pH of from about14.0 to about 8.0 range), the resulting catalyst materials would havepoorer catalytic activities even though they still may haveattrition-resistance properties superior to those otherwise obtainedfrom the proper use of applicant's processes. For example, introductionof a catalytically active ingredient into applicant's strongly acidic(e.g., 1.0-3.0 pH) or strongly alkaline (e.g., 14.0-10.0) clay slurriesnormally will be detrimental to the catalytically activity of thatingredient even if it is not detrimental to the attrition-resistance ofthe resulting matrix.

Thus, applicant's processes can be further categorized by the fact thatif no active catalyst particles are involved, the introduction of aphosphate-containing compound may or may not take the clay slurry out ofits initial "extreme" pH level. For example, the introduction of thephosphate may take an "acidic" clay slurry above its initial 1.0-3.0 pHlevel. On the other hand, the clay/phosphate reaction may just as wellbe carried out in its initial 1.0 to 3.0 pH range without detrimentaleffects on the attrition-resistance qualities of the end productparticles. Such variations in the pH of the reaction system can becontrolled by the identity and relative proportions of thephosphate-containing ingredients. For example, ammonium phosphate isalkaline in nature while phosphoric acid is acidic. Thus, combinationsof various phosphate-containing ingredients can be employed to remain inthe initial 1.0-3.0 pH level, or to move up into higher pH levels offrom about 4.0 to about 8.0. Applicant also has found that mixtures ofmonobasic ammonium phosphate and dibasic ammonium phosphate areparticularly useful for such "pH adjustment" purposes. Thus, any or allof these measures may be used to adjust the pH of a given slurry up ordown so that the pH of the resulting particles can be controlled andthereby exert an influence on the catalytic activities being carried outby such particles.

Applicant believes that the underlying requirement for applicant's pHadjustment steps (at least in the case of the acidic reaction versionsof this invention) follow from the fact that the crystalline latticestructures of the clay particles used in applicant's processes containaluminum components which are normally covalently bonded to oxygen.Therefore, the pH adjustment step of applicant's process is primarilyintended to change this bonding arrangement to one in which the aluminumcomponents are in a plus three valance state (i.e., Al⁺⁺⁺ which is notbonded with oxygen as it is in the clay's untreated state). Achievementof this valance state renders the aluminum component of the clayparticles capable of forming complexes with ammonium; and this in turnbrings about creation of the ammonium aluminum phosphate complex unitsneeded to carry out the herein described processes. That is to say thatapplicant believes that the chemical mechanism of the herein describedprocesses revolve around formation of a complex of aluminum componentsand ammonium (which assumes the role of a monovalent cation) after thealuminum component is rendered into a trivalent cationic form bypreacidification of the clay--at least in all cases where suchpreacidification is necessary. That is to say that some clays may be soconstituted that they require no preacidification, but this will not bethe general case since most clay species will, in fact, require pHadjustment measures (e.g., acidification) in order to change thealuminum-oxygen bonds found in most naturally occurring clays to acationic form, i.e., Al⁺⁺⁺ which is capable of producing the desiredammonium/aluminum/phosphate complex units. Thereafter, the ammoniumunits of the ammonium/aluminum phosphate complex are driven off thecomplex by applicant's calcination step.

Again, this will be the general case; however, there may be specialcases wherein the aluminum component of a given clay species alreadywill be in a suitable condition for direct combination with thephosphate oxygen. Another case which permits direct production ofammonium/aluminum/phosphate complexes will be direct application of astrong base such as ammonium hydroxide to the slurry in order to carryout the "alkaline" versions of applicant's processes. In any event, themore general "acid version" of our processes, as well as the lessgeneral "alkaline versions" are each characterized by their need for apreconditioning, pH adjustment step in order to obtain the"ammonium/aluminum/phosphate complex units" which are so important toapplicant's overall process.

Again, when a simple clay binder system is required there need only be apH adjustment which naturally follows from introduction of the ammoniumand phosphate ion-containing materials into the slurry. However, whenactive catalyst particles are added to the slurry, a second pHadjustment will usually be required to provide the slurry with a pH(e.g., a pH of from about 4.0 to 8.0) which will serve to preserve thecatalytic activity of any active catalyst ingredients added to theslurry. That is to say that such a second pH adjustment will usuallyserve to foster production of attrition-resistant catalyst particleswithout sacrificing the catalytic activity of the catalyst particles.

Thereafter the slurry is dried (e.g., by spray drying) and thencalcined. As the calcination proceeds, a temperature is first reached atwhich surface reactions most probably take place at the aluminumlocations where salt is concentrated. Applicant believes that thechemical mechanism for these reactions are as follows: ##EQU1##

Thus, in the final phase, the orthophosphates decompose to themetaphosphate giving off gases of water and ammonia from the solidmatrix of the "macro-particle." The resulting metaphosphate, having alower melting point, fluxes with the remaining aluminum and fuses into aacid porous, vitreous, "shell" around the remainder of the particle.

It will be noted that if this theory of the chemical mechanism of theseprocesses--at least the acid reaction versions--is correct then themicro-particles will be attached at edges and corners by the fusedmetaphosphate. Similarly, all projecting edges and corners are coatedwith metaphosphate: a hard, vitreous armor cover or shell which servesto protect the macro-particle against abrasion, yet leaving a strongskeletical structure welded together to provide strength against impactand rupture. It also will be noted that the porosity and pore innersurfaces are left intact, permitting the catalyst to retain its fullcatalytic activity. Furthermore, by adjustment of the chemical andphysical parameters of the steps as described, these processes may bemade for manufacture of any desired clay-based catalyst which may beenvisioned.

Some of the most general versions of applicant's process for preparingattrition-resistant binder particles would involve: (1) preparing a clayslurry having from about 20 to about 50 weight percent clay, (2)adjusting the pH of the clay slurry to a level which places an aluminumcomponent of the clay in an oxidation state which is conducive toformation of an ammonium/aluminum/phosphate complex, (3) providing theclay slurry with ammonium ions and with phosphate ions by introducingtherein an ammonium phosphate compound selected from the groupconsisting of monoammonium acid orthophosphate, diammonium acidorthophosphate and triammonium orthophosphate and thereby producing aclay slurry having ammonium/aluminum/phosphate complex units, (4) dryingthe slurry to produce solid particles, and (5) calcining said solidparticles in order to produce attrition-resistant binder particles.

Again, when active catalyst-containing particles are to be produced bythese processes, it will usually be necessary to adjust the pH level ofthe ammonium/aluminum/phosphate complex-containing slurry to another pHlevel (e.g., to 4.0 to 8.0) which does not do harm to the catalyticactivity of the catalyst particles.

Having noted all of the above general points, applicant now can turn tosome of the more exact process details that can be used to furtherdistinguish the above-noted "acidic" and "basic" versions of the hereindescribed processes. In order to begin to make these furtherdistinctions, applicant will describe in patent claim language someparticularly preferred "acid reaction" versions of applicant's overallprocess for preparing attrition-resistant binder materials. Thereaftersome particularly preferred "alkaline reaction" versions of theseprocesses will be described in a similar manner.

ACID REACTION EMBODIMENTS

Perhaps the most preferred acid reaction embodiment of applicant'sinvention will comprise: (1) preparing a clay slurry having from about20 to about 50 weight percent of a clay ingredient, (2) bringing theclay slurry to a pH of from about 1.0 to about 3.0; (3) mixing amonobasic, dibasic and/or tribasic phosphate-containing compound(preferably a mixture thereof which also most preferably includesphosphoric acid) into the clay slurry in an amount which is sufficientto form a viscous, clay/phosphate compound slurry which remains at a pHfrom about 1.0 to about 3.0 and which also is sufficient to provide aquantity of phosphate which is such that the attrition-resistant bindermaterial ultimately made from the slurry will be comprised of from about2 to about 20 weight percent of phosphate with the remaining 80 to 98percent of said attrition-resistant binder material being comprised ofthe clay, (4) drying (e.g., by spray drying, extruding, etc.) theclay/phosphate slurry to produce solid particles (or larger catalystunits such as larger extrudate agglomerates) and then (5) calcining thefinely divided, solid particles (or larger units) to produceattrition-resistant binder "particles". With respect to the pH aspectsof this process, the most important point to be made is that the clayslurry is brought to an extremely "low" pH level (1.0 to .0) before thephosphate is introduced into said slurry. Again, such an adjustment ofthe pH level is an essential step of all such "acidic reaction" versionsof these processes. Again introduction of a phosphate-containingcompound into a clay slurry initially having a higher pH value (e.g.,one in the 5.0 to 8.0 range) will not produce theammonium/aluminum/phosphate complex units which are necessary to theultimate production of end product particles having superiorattrition-resistance properties.

Next, it again should be noted that there are certain versions ofapplicant's processes--particularly those resulting in binder particleshaving less than about 2 percent phosphate--wherein a auxiliary bindercomponent (rather just a phosphate-containing component) is employed "inplace of" some portion of the phosphate component. Again, theseauxiliary binder components will be comprised of a "glue" type binder(alumina, silica, silica-alumina, silica-magnesia, etc.) ingredient anda phosphate-containing ingredient (phosphoric acid, various ammoniumphosphate compounds, etc.). In such cases, the "glue" type bindermaterial also may be thought of as any binder material other than theclay ingredient which is used in that given binder formulation.

For example, use of such an auxiliary binder component to produceapplicant's "simple binder particles" (i.e., those matrices which do notcontain an active catalyst ingredient) can be readily accomplished by aprocess which comprises: (1) preparing a clay slurry having from about20 to about 50 weight percent clay; (2) bringing the clay slurry to a pHof from about 1.0 to about 3.0; (3) mixing a phosphate-containingcompound and an auxiliary binder material (which collectively constitutean auxiliary binder component of the overall resultingattrition-resistant binder material) into the clay slurry in order toform a clay/phosphate-containing compound/auxiliary binder materialslurry which has a pH which generally remains in the 1.0 to 3.0 rangeand which provides quantities of the phosphate-containing compound andthe auxiliary binder material which are such that theattrition-resistant binder particles ultimately made from theclay/phosphate-containing compound/auxiliary binder material slurry willbe comprised of from about 5.25 to about 60.0 weight percent of anauxiliary binder component and from about 40 to about 94.75 weightpercent of a clay component. Here again, the auxiliary binder componentwill have an amount of phosphate which is sufficient to make the binderparticles ultimately made from this particular process comprise from atleast about 0.25 phosphate and up to about 20.0 percent phosphate withthe remainder of the auxiliary component being comprised of theauxiliary binder material (e.g., the auxiliary binder material willcomprise from about 5.0 to about 40.0 percent of the resultingparticles; (4) drying the clay/phosphate auxiliary binder materialslurry to produce solid particles; and (5) calcining said solidparticles in order to complete the production of the attrition-resistantbinder particles.

Another "acid reaction" version of applicant's process for preparingattrition-resistant binder materials can use the phosphate-containingcompound to move the acidic clay slurry from a more acidic level (e.g.,1.0 to 3.0) to a more "neutral" pH level (e.g., from about 4.0 to about8.0). That is to say that this version of applicant's acid reactionprocess uses the phosphate ingredient to take the clay slurry out of theinitial 1.0 to 3.0 pH domain needed to create the desiredammonium/aluminum/phosphate complex units and bring it to a pH level,e.g., from about 4.0 to about 8.0 which will have a higher pH valuewhich may be useful in its own right or which may create an environmentwhich will not destroy the catalytic activity of any catalyst particlessubsequently introduced into the slurry. Generally speaking, suchembodiments of applicant's process will comprise: (1) preparing a clayslurry having from about 20 to about 50 weight percent of a clayingredient, (2) bringing the clay slurry to a pH of from about 1.0 toabout 3.0, (3) mixing a monobasic, dibasic and/or tribasicphosphate-containing compound into the clay in an amount which issufficient to form a clay/phosphate compound slurry having a pH fromabout 4.0 to about 8.0 and also sufficient to provide a quantity ofphosphate which is such that the attrition-resistant binder materialultimately made from the slurry will be comprised of from about 2 toabout 20 weight percent of a phosphate component with the remaining 80to 98 percent of said attrition-resistant binder material beingcomprised of the clay, (4) drying (e.g., by spray drying, extruding,etc.) the clay/phosphate slurry to produce finely divided, solidparticles (or larger catalyst units such as larger "extrudate" typeagglomerates) and then (5) calcining the finely divided, solid particles(or larger extrudate units) to produce attrition-resistant bindermaterial particles.

And here again, the phosphate-containing compound of the process justdescribed can be partially replaced with an auxiliary binder componentcomprised of an auxiliary binder material (alumina, alumina-silica,silica-magnesia, etc.) and a phosphate-containing material (phosphoricacid, various ammonium phosphate(s) and mixtures thereof). That is tosay that an auxiliary binder-employing version of applicant's processcan be employed in a "neutral pH" (4.0 to 8.0) region to carry outapplicant's process. This version will be essentially the same as theacidic version of the auxiliary binder--employing processes--previouslydescribed. The only real difference will be that, rather thanmaintaining the clay slurry at its initial 1.0 to 3.0 pH level, theseauxiliary binder component-employing embodiments will, most preferably,use the phosphate-containing compounds to adjust the pH of the slurryinto the 4.0 to 8.0 range and thereby providing end product particleshaving pH levels which are higher than those which would be obtained ifthe slurry were allowed to remain in its initial 1.0 to 3.0 pH range.

Other highly preferred "acid reaction" embodiments of applicant'sprocess are specifically designed to employ distinct, "active catalyst"particles, that is, to produce more specific embodiments of applicant'sattrition-resistant clay/phosphate/catalyst matrix particles. In otherwords, these more particular embodiments use applicant's "acid reaction"processes to incorporate active catalyst particles into a continuousphase comprised of a clay/phosphate binder system in order to formlarger (e.g., microspheroidal sized) active catalyst-containing particleunits. These embodiments generally will comprise: (1) preparing a clayslurry having from about 20 to about 50 weight percent of a clayingredient, (2) bringing the clay slurry to a pH of from about 1.0 toabout 3.0, (3) mixing a monobasic, dibasic and/or tribasicphosphate-containing compound (again ammonium-containing phosphatecompounds are highly preferred for this purpose) into the clay slurry inan amount which is sufficient to form a clay/phosphate compound slurryhaving a pH from about 4.0 to about 8.0 and sufficient to provide aquantity of phosphate which is such that the clay/phosphate/ catalystmatrix particles ultimately made from the slurry will be comprised offrom about 2 to about 20 weight percent phosphate; (4) mixing asufficient amount of catalyst particles into the clay/phosphate compoundslurry in order to form a clay/ phosphate compound/catalyst particleslurry which has a quantity of catalyst particles which is such that theattrition-resistant clay/phosphate/catalyst matrix particles ultimatelymade from this process will contain from about 3 to about 60 weightpercent of said catalyst particles, (5) drying (by spray drying,extruding, etc.) said clay/phosphate compound/catalyst particle slurryin order to produce solid particles, and (6) calcining the solidparticles to produce attrition-resistant binder/ catalyst matrixparticles which contain between about 3 and about 60 percent of thecatalyst particles and between about 20 and about 95 percent clay andabout 2 to about 20 percent phosphate.

It should be very strongly emphasized that in these active catalystparticle-containing embodiments of applicant's process the slurry shouldbe adjusted to the 4.0 to 8.0 pH level before the catalyst is introducedtherein. Again, applicant has found that if active catalyst particlessuch as zeolites are introduced into these slurries while they are inthe initially low pH state (e.g., from 1.0 to 3.0), the catalyticactivity of the resulting catalyst will suffer considerably. Indeed, thebest pH levels for introduction of catalysts into such clay slurries arethose which are neutral or nearly so (e.g., those having pH levels offrom about 6.5 to about 7.0 are particularly preferred). This all goesto say that in these particular embodiments, active catalyst particlesshould be introduced into the clay slurry only after introduction of amore alkaline material and especially a phosphate-containing compound,has raised the pH of the clay slurry to values of from about 4.0 toabout 8.0. Again, however, this does not mean that applicant's initialacidification step (which creates the initial 1.0 to 3.0 pH value) canbe neglected when active catalyst particles are employed--indeed, if theslurry were simply brought directly to the 4.0 to 8.0 level, withoutfirst attaining these low pH conditions the desired ammonium/aluminumphosphate complex units previously described would not be produced andthe resulting particles would have rather poor attrition-resistancequalities.

This catalyst-employing, acid reaction, version of applicant's processalso can be modified to employ an "auxiliary binder component" comprisedof an auxiliary binder material and a phosphate. Such a process willcomprise: (1) preparing a clay slurry having from about 20 to about 50weight percent clay; (2) bringing the clay slurry to a pH of from about1.0 to about 3.0; (3) mixing a phosphate-containing compound and anauxiliary binder material (which collectively constitute an "auxiliarybinder component" of the end product, attrition-resistantclay/phosphate/auxiliary binder material catalyst matrix particles) intothe clay slurry to form a clay/phosphate-containing compound/auxiliarybinder material slurry in an amount which is sufficient to form aclay/phosphate-containing compound/auxiliary binder material slurryhaving a pH from about 4.0 to about 8.0 and to provide quantities ofphosphate and auxiliary binder material which are such that theclay/phosphate/catalyst matrix particles ultimately made from the slurrywill be comprised of from about 5.25 to about 40 weight percent of theauxiliary binder component; (4) mixing catalyst particles into theclay/phosphate compound/auxiliary binder material slurry to form aclay/phosphate-containing compound/auxiliary binder component/ catalystparticle slurry which has a quantity of catalyst particles which is suchthat the attrition-resistant clay/phosphate/ catalyst matrix particlesultimately made from this process will contain from about 3 to about 40weight percent of said catalyst particles; (5) drying saidclay/phosphate compound/ catalyst particle slurry to produce finelydivided, solid particles; (6) calcining the solid particles to produceattrition-resistant binder/catalyst matrix particles which containbetween about 3 and about 60 percent by weight of the catalystparticles, between about 5.25 and about 40 weight percent of theauxiliary binder component and from about 20 to about 91.75 percent clayand wherein the auxiliary binder component has sufficient phosphate togive the clay/auxiliary component/catalyst particles a phosphateconcentration of at least 0.25 percent by weight. Here again, whenauxiliary binder materials are employed the most preferred phosphatepercentages will generally be from about 0.25 to about 2.0 percent.

Applicant's acid reaction processes have various "most preferred"embodiments, features, steps, techniques, etc. These may include any oneor all of the following: (1) creating a water/ kaolinite clay slurry bydiluting a kaolinite clay slurry having about a 70% clay concentrationto about a 40% clay concentration by the addition of water to the 70%slurry, (2) bringing the resulting clay/water slurry to a pH of fromabout 1.0 to about 3.0 through the use of phosphoric acid rather thansome other acid, (3) introducing a mixture of monobasic ammoniumphosphate (i.e., monoammonium acid orthophosphate) and dibasic ammoniumphosphate (i.e., diammonium acid orthophosphate) into the 40% clay/waterslurry in quantities such that the pH of the resulting clay/phosphatecompound slurry is brought to a pH level of from about 4.0 to about 8.0(but more preferably to a pH level of from about 6.5 to about 7.0) andsuch that the phosphate components of the ammonium phosphate compounds(including phosphoric acid if it is employed) represent from about 6.0to about 12.0 weight percent of the slurry, (4) spray drying theresulting clay/phosphate slurry in a manner which produces particlespredominantly in a 60-80 micron size range, (5) calcining said particlesat about 1350° F. to produce the final product particles and (6) usingthe temperature conditions existing in a catalytic unit to performapplicant's calcination step, as opposed to performing a distinctcalcination step in a calcination unit specially designed for suchcalcination operations.

Alkaline Reaction Embodiments

The "alkaline reaction" embodiments of applicant's process can be usedin ways which--except for their "alkalinity" features--are generallyanalogous to the "acid reaction" versions of applicant's variousprocesses. For example, they too can be employed to produce eithersimple binder particles (which contain no active catalyst ingredients)or catalyst-containing binder systems (which do in fact contain activecatalyst particles). And, they too can employ clay/ phosphate bindersystems or auxiliary binder components comprised of "glue type" bindermaterials and phosphate-containing compounds.

One particularly preferred version of applicant's alkaline reactionprocess for producing simple binder particles involves creating anextremely alkaline clay slurry (e.g., one having a pH of from about 13.0or 14.0 to about 10.0) and then introducing a phosphate-containingcompound into this slurry alkaline without appreciably lowering theslurry's pH through the use of an acid such as phosphoric acid. This"alkaline reaction" version of applicant's process for preparingattrition-resistant "simple binder particles" (i.e., binder particlesnot containing an active catalyst ingredient) will generally comprise:(1) preparing a clay slurry having from about 20 to about 50 weightpercent of a clay ingredient, (2) bringing the clay slurry to a pH offrom about 13.0 to about 10.0, (3) mixing an amount of a monobasic,dibasic and/or tribasic phosphate compound into the clay slurry which is(are) sufficient to form a viscous, clay/phosphate slurry and to providea quantity of phosphate which is such that the slurry will be comprisedof from about 2 to about 20 weight percent of phosphate and about 80 toabout 98 percent clay, (4) drying (e.g., by spray drying, extruding,etc.) the clay/phosphate compound slurry to produce finely divided,solid particles and then (5) calcining the solid particles to produceattrition-resistant binder particles.

Another "alkaline reaction" version of applicant's process for preparingattrition-resistant binder particles involves driving the pH of the clayslurry below its initial, 13.0 to 10.0 level in order to produce "simplebinder particles" having lower pH values. This version of the processwill comprise: (1) preparing a clay slurry having from about 20 to about50 weight percent of a clay ingredient, (2) bringing the clay slurry toa pH of from about 13.0 to about 10.0, (3) mixing a monobasic, dibasicand/or tribasic phosphate compound and/or an amount of an acid into theclay slurry which is such that the slurry will be comprised of fromabout 2 to about 20 weight percent of phosphate and about 80 to about 98percent clay; (4) adjusting the pH of the resulting slurry to a level offrom about 4.0 to about 8.0; (5) drying (e.g., by spray drying,extruding, etc.) the clay/phosphate compound slurry to produce solidparticles and then (6) calcining the solid particles to produceattrition-resistant binder particles. Here again, the "adjusting" of thepH level to 4.0 to 8.0 can be accomplished by introduction of aphosphate-containing compound such as phosphoric acid.

Both of these "alkaline reaction" versions may also employ auxiliarybinder formulations as a part of their overall formulations. Forexample, the use of less than about 2.0 percent phosphate also mayinvoke a need for the use of an auxiliary binder component (here again,those comprised of the previously noted auxiliary binder materials andphosphate-containing compounds are preferred) which can be used in thesame general proportions employed in the "acidic reaction" versions ofthis process. Here again, however, the phosphate content of theauxiliary binder must be sufficient to provide the end product particleswith a phosphate component of at least 0.25 percent by weight. Theremainder of the auxiliary binder component will be an auxiliary bindermaterial comprised of one or more of the alumina, silica,silica-alumina, etc. materials previously described under the generalrubric of "glue" materials. The phosphate ingredient can constitute fromabout 0.25 to about 20 percent of the end product; but, as in the caseof the "acid reaction" versions of these processes, phosphatepercentages of from about 0.25 to about 2.0 percent are highly preferredwhen such auxiliary binder materials are employed. Consequently, such asimple clay and auxiliary binder component catalyst might be comprisedof from about 5.0 to about 40 percent of an auxiliary binder material,0.25 to 20 percent phosphate and from about 40 to about 94.75 weightpercent clay.

Another preferred "alkaline reaction" version of applicant's process isdesigned to produce attrition-resistant clay/phosphate/catalyst matrixparticles. That is to say that alkaline reaction versions of theseprocesses can be used to incorporate catalyst particles into a binderwhich, in effect, constitutes a continuous phase comprised of the clayand phosphate components. This embodiment of applicant's process willgenerally comprise: (1) preparing a clay slurry having from about 20 toabout 50 weight percent of a clay ingredient, (2) bringing the clayslurry to a pH of from about 13.0 to about 10.0, (3) forming a binderformulation by mixing an amount of an acid and an amount of a monobasic,dibasic and/or tribasic phosphate compound into the clay slurry whichare collectively sufficient to form a viscous, clay/phosphate slurryhaving a pH from about 4.0 to about 8.0 and to provide a quantity ofphosphate which is such that the slurry will be comprised of from about2 to about 20 weight percent of phosphate, (4) mixing catalyst particlesinto the clay/phosphate compound slurry to form aclay/phosphate/catalyst particle slurry having a quantity of catalystparticles which is such that the catalyst particles of theattrition-resistant clay/phosphate/catalyst matrix ultimately made fromthis process will contain from about 3 to about 60 weight percent ofsaid catalyst particles, (5) drying (by spray drying, etc.) saidclay/phosphate compound/catalyst particle slurry to produce finelydivided, solid particles, and (6) calcining the finely divided solidparticles to produce attrition-resistant binder/catalyst matrixparticles which contain between about 3 and about 60 weight percent ofcatalyst, about 2 to about 20 weight percent of phosphate and about 20to about 95 weight percent clay. For reasons somewhat akin to thosesuggested for the "acid reactions" used to create active catalystcontaining matrices, such alkaline reaction processes for producingactive catalyst-containing matrices should not introduce the catalystparticles into the slurry while it is in an "extreme" condition withrespect to its pH level. That is to say that, in general, the catalystshould not be introduced into the slurry while it is at its initial,e.g., 14.0-10.0 (that is "extreme") pH level, but rather the catalyst,in general, should be introduced only after the ammonium/ aluminumphosphate complex units are formed and only after the pH level isadjusted (using any suitable source of acidity, e.g., a mineral acid,but especially phosphoric acid) into a more "neutral", i.e., 4.0 to 8.0(and preferably 6.5-7.0) pH level.

Auxiliary binder component-containing formulations also can be employedin these "alkaline reaction" versions of applicant's process. Theseembodiments introduce catalyst particles into an auxiliary bindercomponent-employing overall binder formulation, and hence into thematrix particles made from them. By way of example, such a process mightcomprise: (1) preparing a clay slurry having from about 20 to about 50weight percent clay; (2) bringing the clay slurry to a pH of from about14.0 to about 10.0; (3) mixing an amount of a phosphate-containingcompound, an acid (preferably phosphoric acid) and an auxiliary bindermaterial into the clay slurry which are collectively sufficient to forma clay/phosphate/auxiliary binder material slurry having a pH from about4.0 to about 8.0 and to provide a quantity of phosphate and auxiliarybinder material which is such that the end product particle willcomprise from about 5.25 to about 40 weight percent of the resultingattrition-resistant binder material; (4) mixing catalyst particles intothe clay/phosphate compound slurry to form a clay/ phosphate/catalystparticle which is such that the catalyst particles of theattrition-resistant clay/phosphate/catalyst matrix ultimately made fromthis process will contain from about 3 to about 40 weight percent ofsaid catalyst particles; (5) drying said clay/phosphatecompound/catalyst particle slurry to produce finely divided, solidparticles; and (6) calcining the finely divided solid particles toproduce attrition-resistant binder/catalyst matrix particles whichcontain between about 3 and about 40 weight percent of the catalystcomponent, between about 20 and about 91.75 weight percent clay and fromabout 5.25 to about 40 weight percent of an auxiliary binder componentwhich has a phosphate content which is capable of providing the endproduct attrition-resistant particles with a phosphate content of atleast 0.25 weight percent. Here again, the preferred phosphatepercentage is 0.25 to 2.0 percent, but percentages ranging from about0.25 to 20.0 can be employed. The remainder of the auxiliary bindercomponent will comprise a "glue" type binder such as alumina, silica,silica-alumina, silica-magnesia, etc. As was previously noted, suchauxiliary binder materials may also be thought as being any bindermaterial other than the clay being utilized in that particular particle.Consequently, the particles resulting from such formulations will becomprised of from about 20 to about 91.75 percent clay, from about 0.25to about 20 percent phosphate, from about 5 to about 20 percentauxiliary binder material and from about 3 to about 40 weight percentactive catalyst particles.

The "most preferred" procedures for carrying out applicant's process bycoming from the "basic side" (e.g., 14.0 to 10.0) of the pH scale alsomay include further modifications such as: (1) creating a kaolinite clayslurry by diluting a kaolinite clay slurry having about a 70% clayconcentration to about a 40% concentration by the addition of water tothe 70% slurry, (2) bringing the resulting clay/water slurry to a pH offrom about 14.0 to about 10.0 by the use of ammonium hydroxide, (3)introducing a phosphate-containing compound (e.g., monobasic ammoniumphosphate, dibasic ammonium phosphate, etc., or most preferably mixturesthereof) into the clay slurry in quantities such that the phosphatecomponent of the slurry represents from about 6.0 to about 12.0 weightpercent of the slurry and (4) introducing sufficient phosphoric acidinto the clay/phosphate-containing compound slurry to bring its pH downto a level from about 4.0 to about 8.0. Again, the use of phosphoricacid is particularly preferred for this purpose since it performs thedual functions of lowering the pH of the alkaline system to the desired4.0 to 8.0 level while contributing to the provision of the phosphatewhich is needed to attain the 2 to 20 (or 0.25 to 20) weight percentphosphate proportions in the resulting particles. These most preferredversions also may take into account the concern for the fact that if acatalyst is employed, it should not be introduced into the slurry whileit is in its extreme (14.0-10.0 pH) alkaline state; but rather thecatalyst should be introduced into the slurry only after it is broughtto a 4.0 to 8.0 pH level, preferably through the use ofphosphate-containing and/or acid ingredients such as ammonium phosphateand phosphoric acid.

As "optional", but by no means mandatory, steps, both the acid reactionand alkaline reaction versions of applicant's overall processes mayfurther comprise: (1) using only phosphoric acid to adjust a slurry to adesired pH level, (2) placing "optional ingredients" such as viscosityagents, gas evolution agents and/or density providing materials in theslurry, (3) vigorously mixing the appropriate reactants--right up to themoment of the spray drying step--in order to help preserve an intimatelymixed state of the original ingredients, (4) drying the products of thespray drying in a distinct drying step before calcining them (5) use ofmixtures of clays to make up the clay/phosphate slurries, (6) use ofmixtures of phosphate-containing compounds, (7) use of mixtures ofacids, (8) use of clay particles of from about 0.2 to about 0.3 micronsin average diameter, (9) use of one or more fluids (e.g., water andalcohol) in order to form at least a portion of any given clay slurryand (10) employing the temperature conditions existing in a catalyticcracking reaction system to supply the heat and atmosphere necessary toperform applicant's calcination step.

As was previously noted, the binder matrices made by most of applicant'sprocesses--for the most part--will tend to be catalytically inert.However, they can be "designed" to be catalytically active; for example,use of certain catalytically active kaolinite clays (halloysite,rectorate, etc.) will tend to produce binders having their own inherentcatalytic activities. On the other hand, use of other, less active clayswill generally produce binders which are catalytically inert. Forexample, use of kaolin clay will generally produce catalytically inertbinder materials. Generally speaking catalytic "inertness" should beregarded as a "virtue" of applicant's binder formulations. Moreover,inert binder systems may be rendered catalytically active by certainwell known techniques such as "impregnation" of an inert binder with acatalytically active material.

With respect to the subject of "impregnation", it should at least bementioned in passing that many metallic atoms, such as those ofvanadium, can be associated with any binder particles or binder/catalystparticles produced b the methods of this patent disclosure by the use ofimpregnation techniques known to the art. Thus, by way of a moredetailed example of such impregnation techniques, vanadium pentoxide V₂O₅, in oxalic acid, could be associated, by impregnation procedures,with applicant's binder material(s) or binder/catalyst matrixmaterial(s) after they have been calcined. The resulting vanadiumimpregnated matrix can then be redried (preferably at about 250° F. fromabout 60 minutes to about 240 minutes) and then re-calcined (preferablyfor about 180 minutes at about 1350° F.). During the second calcinationthe oxalate ingredient will break down to CO₂ and steam which are eachdriven off as gases and thereby leaving the vanadium as a cation, VO₂ ⁺.Impregnated binder particles made by such impregnation techniquespreferably will comprise from about 0.5 to about 4 percent vanadium byweight, with about 2 percent by weight being a particularly preferredproportion.

Applicant's processes--and the binder materials made from them--areespecially useful in binding catalyst particles together into moreappropriately sized catalytically active particles. Indeed, this isprobably the most preferred use for applicant's binder materials. Thetypes of catalytically active ingredient(s) which can be used inapplicant's binder formulations can vary greatly. Amorphous claymaterials (e.g., those containing alumina), faujasites, naturallyoccurring zeolites, synthetic zeolites such as ZSM-5, low-soda exchangedY-zeolites or ultra-stable Y-zeolites as well as mixtures of suchmaterials are but a few of the more common kinds of catalysts which canbe incorporated into applicant's binder systems. The clays,phosphate-containing compounds and acids which can be employed in thepractice of this invention also can vary greatly. Various specificexamples of formulations in which these various materials are used willbe given in more detail in the DESCRIPTION OF THE PREFERRED EMBODIMENTSsection of this patent disclosure. For now, however, only some of themore pronounced general attributes and uses of the various clays,catalysts, phosphate-providing compounds and acids which can be used inthese processes need be mentioned.

CLAYS

The clay ingredients which can be employed in applicant's process canvary considerably. For example, a wide variety of kaolinite clays (e.g.,kaoline, halloysite, rectorate, etc.) montmorillionite clays (e.g.,natural montmorillionite as well as synthetic montmorillionite clays),sepiolite clays and attapulgite clays can be employed. Of these, thekaolinite clays and most particularly kaolin clays, are preferred--iffor no other reason than their low cost and "universal" ability to bindso many different kinds of catalyst particles without entering intoundesired chemical reactions with such catalysts.

PHOSPHATE-CONTAINING COMPOUNDS

The phosphate-containing compounds used for applicant's process are mostpreferably selected from the group consisting of monobasic phosphatecompounds, dibasic phosphate compounds and tribasic phosphate compounds.Because of their ready availability and relatively low costs, monobasicammonium phosphate, dibasic ammonium phosphate and tribasic ammoniumphosphate and/or phosphoric acid are particularly preferred forapplicant's purposes. That is to say that other phosphate-containingcompounds can be employed in the practice of this invention, but for themost part they are, to varying degrees, much less preferred from varioustechnical and/or cost points of view. It also should be emphasized thatapplicant has found that mixtures of the above notedphosphate-containing compounds are especially preferred. For example,mixtures of monobasic ammonium phosphate and dibasic ammonium phosphateare particularly well suited for adjusting applicant's "acidic reaction"clay slurries from an initial 1.0 to 3.0 pH level to a 4.0 to 8.0 pHlevel. And, here again, mixtures of monobasic or dibasic ammoniumphosphate and phosphoric acid are particularly effective in loweringapplicant's "alkaline version" slurries from their initial 14.0 to 10.0pH levels to those 4.0 to 8.0 pH levels which are better suited for theintroduction of catalyst particles.

It should also be noted in passing that the terminology used to describethe ammonium phosphate compounds used in these processes varies somewhatin the chemical literature. For example: (1) monoammonium acidorthophosphate is often referred to as "monobasic ammonium phosphate",(2) diammonium acid orthophosphate is often referred to as "dibasicammonium phosphate", and (3) triammonium orthophosphate is sometimesreferred to as "tribasic ammonium phosphate." The terminology used inthis patent disclosure may likewise vary according to these twonomenclature systems without implying a difference or distinction in thematerials themselves.

ACID AND ALKALINE INGREDIENTS

The acids, other than phosphoric acid, which can be used to obtainapplicant's original 1.0 to 3.0 pH levels, can be virtually any mineralor organic acid capable of supplying the "acidity" needed to bring aslurry to a desired pH level. Nitric acid is, however, particularlypreferred for such purposes. In the same vein, virtually any strong basecan be employed to obtain the original 14.0 to 10.0 pH level in thealkaline version of applicant's process, but ammonium hydroxide isparticularly preferred for this purpose because of its readyavailability and relatively low cost compared to many other stronglyalkaline compounds. However, sodium generally constitutes a highlyundesirable ingredient in most catalyst particles. Hence, use of sodiumhydroxide is not recommended for producing the initial high (e.g.,4.0-10.0) alkaline conditions. Finally, before leaving the discussion ofthe alkaline versions of applicant's processes, it should be pointed outthat any mineral or organic acid can be used to lower the alkaline clayslurry from its initial 14.0 to 10.0 pH level to the desired 4.0 to 8.0level; however, here again, phosphoric acid is particularly preferredfor this purpose because not only does it supply the slurry system withthe acidity required to lower the pH of the system, it also suppliesphosphate ions and thereby supplements the phosphate supplied by anyother phosphate-containing compounds used in this version of theprocess.

CATALYSTS Amorphous Catalysts

Applicant's processes can be used to bind a wide variety of amorphouscatalyst materials. This ability is particularly important to certainpetroleum industry applications of this invention since amorphouscatalysts are so widely used to crack those higher molecular weightcompounds that cannot be cracked on the surface of zeolitic componentsof a catalyst. Within this group of amorphous catalytic materials thereare two generally recognized subgroups; synthetic catalysts andnaturally occurring catalysts, in particular various kinds ofcatalytically active clays. In the synthetic amorphous catalystcategory, various alumina type materials are probably the most importantfrom the commercial point of view. They are usually made by so-called"gel reactions" of the types previously noted, but especially thoseinvolving alumina and/or various "activated" aluminas. These gelreaction alumina products have the property of being dispersible inmonovalent acids. They also are characterized by their significantsurface areas, e.g., greater than 150 square meters per gram, and bytheir very significant surface acidity. In the case of aluminas producedby such gel reactions, the surface acidity of these materials may beincreased even further by adding small amounts of silica to thestructure. However, it should again be emphasized that applicant'sreactions should not be regarded as being analogous to such prior artgel reactions. As was previously noted, they are qualitatively differentin several respects.

As far as "catalytically active clays" are concerned, the most importantto applicant's invention are those various members of the kaolinitegroup which are catalytically active, e.g., halloysite, rectorate andhectorite. Various montmorillonite clays also can be used for somecatalytic purposes. It also should be noted that in addition tonaturally occurring clays, synthetic clays such as syntheticmontmorillonite and certain of the so-called pillared clays also can beemployed for various catalytic purposes and, hence, may be incorporatedinto applicant's binder formulations. Those catalytically active clayssuch as sepiolite and attapulgite clays used as metal scavengingcatalyst in petroleum refining operations also can be easily bound byapplicant's binder formulations. Therefore, any of these clays might beused in applicant's binder formulations if, in fact, their catalyticactivities were desired. That is to say they could be used asapplicant's clay ingredient(s) and/or they could be used as applicant'sauxiliary binder materials, i.e., along with those alumina, silica,alumina-silica, etc. "auxiliary binder materials" previously discussed.

Synthesis Faujasites

The synthetic faujasites are a most important group of crystallinecatalytic materials which also can be readily bound in applicant'sbinder matrices. This group generally comprises materials having silicato alumina ratios from about 3.0 to 100. Usually the lowersilica/alumina ratios, e.g., 3.0 to 6.0, are made by directcrystallization. Materials with higher silica to alumina ratios may beprepared by removing alumina from the crystal lattice, e.g., by steamingat elevated temperatures and by acid leaching or a combination of theseprocedures. Alumina may also be removed from these materials by the useof chelation agents. In still other processes for the production of suchcatalytic materials, alumina can be removed from their lattices andsilica can be inserted into the lattice in place of said alumina. In allsuch cases, however, these crystalline materials have small particlesizes and, hence, can be agglomerated into large particles through theuse of applicant's invention.

Indeed, as was previously noted, there is an extremely large variety ofcatalytically active materials that have the common property that theyare too small in particle size to be used directly in commercialoperations and, hence, require some type of a binder to hold theirparticles together in larger, attrition-resistant particles andespecially those sized in the range of about 60 to about 100 microns(and more preferably from about 60 to about 80 microns). For the generalpurposes of this patent disclosure the term "small" crystalline catalystingredients can be taken to mean those catalytic particles havingaverage particle sizes of less than about 5 microns. In any case, allsuch "small" particles must be formed into larger particles in order tobe made useful as cracking catalysts. Again, applicant's binderformulations are particularly well suited to production of largerparticles through spray drying operations, e.g., microspheroidal sizedunits having average diameters of from about 60 to about 100 microns areusually produced by such spray drying procedures. However, as waspreviously noted, particles of less than about 20 microns are notpreferred for use in "fluid" processes; not because they will not workcatalytically, but rather because they are subject to cyclone-inducedelutriation losses.

Synthetic Zeolites

Synthetic zeolites represent another large group of catalysts which arewidely used in the petroleum processing industry. They are normallyprepared by using organic templates that alter the crystal habit of thecrystallite and thus imparting desirable catalytic properties to theresulting material. Perhaps the best known example of such syntheticzeolite materials is ZSM-5. There are, however, well over a hundredother zeolites in this general category. Moreover, the groups ofcrystalline materials designated as "mordenites" and as "beta zeolites"also are of considerable commercial importance and, hence, are suitedfor inclusion in applicant's binder systems. Those skilled in this artalso will appreciate that, within any given type of crystalline zeolitethere also may be further distinctions based upon variations insilica-to-alumina ratios or other parameters that influence thecatalytic activities of such materials. Suffice it to say that any ofthese synthetic zeolites can be bound together into microspheroidal orextrudate particles through the use of applicant's binder formulation.

Now, having more fully identified the chemical nature of the ingredientswhich can be used in applicant's various processes, it again should benoted that the relative proportions of these ingredients are generallyexpressed throughout this patent disclosure in terms of their weightpercentage contributions to the "solid" ingredients ultimately containedin the final product attrition-resistant matrices. That is to say that,unless otherwise noted, the percentages expressed herein usually do notinclude the weight of such ingredients as: (i) the liquid medium (e.g.,water, alcohol, etc.) used to make up the slurries in which the clayparticles are placed, (ii) the acids other than phosphate-providingportions of phosphoric acid which are employed in making up the binderformulations or (iii) the non-phosphate components of thephosphate-containing compounds employed in these processes.

For example, with respect to applicant's preferred phosphate-containingcompounds, the herein described percentages would not include theammonium component of any mono, di and/or tribasic ammonium phosphatecompound(s) used to give a binder material its 0.25 to 2.0 percent, orits 20.0 to 19.75 percent, phosphate proportion. Thus, for example, the2-20 weight percent phosphate supplied by an ammonium phosphate compoundwould include only the phosphate components of these molecules and nottheir ammonium components. These "weight neglecting" assumptions are notas artificial as they might appear at first because applicant's spraydrying and calcining steps will tend to completely drive off anyvolatile ingredients or compound components. Indeed, the ammoniumphosphates are highly preferred phosphate compounds because theirammonium components are driven off the particle by the calcinationprocedures of these processes. In other words the calcination step wouldcompletely drive off the ammonium component of these molecules, but thephosphate components will remain in the end product matrices. By way offurther example of this point, the spray drying and/or calcination stepswould each serve to drive off any fluid (such as water, alcohol, etc.)used in making up the clay slurry as well as the ammonium component ofany ammonium phosphate ingredient(s). In any event, applicant haselected to express the relative proportions of the ingredients of thispatent disclosure on this "dry weight" basis.

Any other ingredients in applicant's matrices, if indeed any areemployed, will generally comprise only relatively small proportions(e.g., from about 1 to about 10 weight percent of the overall resultingmatrix). In discussing these relative proportions with respect tocatalyst particle-containing matrices, it also should be noted that anyother ingredients (i.e., those other than the clay, phosphate, auxiliarybinder material and catalyst particles) are better thought of asconstituting a portion of the weight of the "non-phosphate"ingredient(s) rather than a portion of the weight of the remainder ofthe resulting matrices. Thus, applicant's more preferred simple binderformulations would contain from 2-20 percent, and more preferably from 6to 12 weight percent of a phosphate component, even if ingredients otherthan clays were employed; in other words, the 2-20 percent phosphateproportion should not be "sacrificed" in order to introduce any otherpotential ingredients (e.g., viscosity agents, gas forming agents,density-providing particles, etc.) into the resulting matrix. Looking atthis requirement from another prospective, it might also be said thatapplicant's 2-20 percent phosphate requirement will only be "sacrificed"only if an "auxiliary binder component" is also employed. In such casesthe "auxiliary binder component" can be thought of as being a part of anoverall clay/auxiliary binder component system which can be used in itsown right or used to bind active catalyst particles together into moreappropriately sized units. However, in all cases applicant's threshold0.25 percent phosphate requirement should never be "sacrificed" in orderto introduce any other potential ingredient. In general such otheringredients can replace a portion of the clay, so long as the resultingclay proportion does not fall below about 20 percent in the end productparticles.

Additional Theoretical And Practical Considerations

Several preferred, but optional, steps can be incorporated into theseprocesses, one of these involves further drying of the products of thespray drying, extrusion, etc. step by a separate and distinct drying (ordesiccating) step in order to obtain more completely "anhydrous" formsof the particles produced by the spray drying, etc. Such anhydrous formsof the products of the drying step can then be calcined in the samemanner as those products received directly from applicant's drying step.Such additional drying may, in many cases, serve to better "freeze" theingredients in the homogeneous state in which they originally existed inthe reaction mixture. That is to say that the "solid" particle productof applicant's spray drying step, flashing, etc., may then be, as anoptional process step, desiccated or dried in a manner other than thedrying which is inherent in the drying, spray drying or flashing step inorder to remove any remaining traces of the liquid medium which may bestill present in the interstices of the particles and/or associated withthe particulate product of the spray drying step as water of hydration.Drying times for this distinct drying step will normally take from about0.2 hours to about 24 hours at temperatures preferably ranging fromabout 200° F. to about 500° F. (at atmospheric pressure), but in allcases, at temperatures greater than the boiling point of the liquidmedium employed (e.g., greater than 212° F. in the case of water). Inany case, such drying will usually suffice to produce a completelyanhydrous, product. That is to say any remaining liquid medium which mayhave been physically associated with and/or loosely chemically bondedwith (e.g., as water of hydration) the solid phase product of thevolatilization step, whether it be, at this point in the overallprocess, in a crystalline lattice form, or in an amorphous solid form,or even in a gel form, can be driven off by a separate and distinctdesiccation, drying, etc. step(s). In any event, the result ofapplicant's use of such additional drying or desiccation step(s) will bean aggregate of particles of anhydrous ingredients which are not able todepart from their original physical identity as a homogenousdistribution of the ingredients in the original reaction mixture.

After such drying or desiccation--if it is in fact employed--it remainsonly to take the solid particles and calcine them. Some of the chemicalreactions which may be taking place as a result of such calcinationprocedures have already been described. Therefore, suffice it to saythat the final step of this process seeks to produce those temperatureconditions which are needed to vitrify the products of theclay/phosphate reaction which took place when the phosphate-containingcompound(s) were introduced into the clay slurry. The calcination stepalso serves to drive off, as gaseous materials, the most volatile (e.g.,ammonium, water, etc.) components of the solid particles produced by thespray drying and thereby leaving only those elements which are desirablein forming attrition-resistant binder materials or binder/catalystmaterials. Such calcination is preferably accomplished by calcining theparticle products of the spray drying step (or the extruding step) attemperatures ranging from about 1,000° F. to about 1,950° F. (atatmospheric pressure) for from about 60 minutes to about 240 minutes,and most preferably at about 1,350° F. for about 180 minutes. Thiscalcination step can be carried out in those calcination apparatus knownto this art which are specifically designed for such purposes. This isthe preferred procedure.

It should also be understood that the temperature conditions (andperhaps even the atmosphere content) of a catalytic reactor unit maythemselves provide applicant's calcination step. That is to say that thecalcining can be carried out in a catalytic unit which employs theattrition-resistant binder particles. Indeed, in some versions of theherein described processes, the particulate products of a spray dryingstep may be injected directly into an operating catalytic unit as thoseparticles are formed. Thereafter, the particles will be "calcined" bythe temperature conditions existing in the catalytic unit as it carriesout some other catalytic task. Again, this could constitute a preferredprocedure if the binder formulations of patent disclosure aremanufactured in the same plant where they are used and where thecatalytic unit into which they are introduced has appropriate operatingtemperatures.

Spray drying procedures well known to this art will generally serve asthe fastest, most efficient way to dissipate the liquid media in theclay slurry so as to "fix" the various ingredients in a solid matrix(again, extrusion techniques are less preferred, but still operable).That is to say that such "fixing" or "freezing" of the ingredients in ahomogenous mixture is preferably accomplished by rapid dissipation ofthe liquid medium under the conditions of spray drying wherein the totalmixture is atomized to small liquid spherical droplets in an atmosphereof sweeping heated gases (which may be air) with a concomitant rapidevaporation of the liquid medium at the boiling point of whatever liquidphase is present at nominally atmospheric pressure. Such spray dryingoperations can be carried out by any number of techniques well known tothis art (e.g., such as those disclosed in the 635 patent which is, inits entirety, incorporated by reference into this patent disclosure) inorder to produce MS (microspheroidal) particles in a range of sizes,e.g., 60-80 microns and most preferably such that essentially all suchparticulate materials resulting from said spray drying (and fromsubsequent calcining) will be retained by a Standard U.S. 200 meshscreen and essentially all will be passed by a Standard U.S. 60 meshscreen.

By way of further clarification, the spray drying equipment which can beused in applicant's process may employ at least one restriction or highpressure nozzle having a diameter in the range from about 0.01 in. toabout 0.2 in. and preferably from about 0.013 in. to about 0.15 in. Thepressure upstream of such a high pressure nozzle may range from about400 psig. to about 10,000 psig. and preferably be maintained betweenabout 400 psig. and about 7,000 psig. The material to be spray dried issent through the nozzle system into a space or chamber. The pressure inthe space or chamber downstream from the nozzle system is lower thanthat immediately up-stream of the nozzle and is typically in the rangefrom about 0 psig. to about 100 psig., and preferably be from about 0psig. to about 20 psig. Once through the nozzle, the material may becontacted for a relatively short time, e.g., from about 0.1 seconds toabout 20 seconds with a gas stream which is at a temperature of fromabout 200° F. to about 1500° F. and preferably from about 200° F. toabout 750° F. in order to complete the spray drying step. The gas streamwhich may be, for example, air or the flue gases from an in-line burner(used to provide a gas stream having the proper temperature) or asubstantially oxygen-free gas, may flow co-current, counter-current or acombination of the two relative to the direction of flow of the materialto be dried. The spray drying conditions, such as temperatures,pressures and the like, may be adjusted because of, for example,variations in the composition of the material to be dried in order toobtain optimum results which are achievable through routineexperimentation.

An alternative to the high pressure nozzle described above is aso-called "two-fluid" nozzle in which the material to be dried isdispersed by a stream of gas, typically air. Such a two fluid nozzle hasthe advantage of being able to employ a low operating pressure, e.g.,from about 0 psig. to about 60 psig. for the material to be dried andfrom about 10 psig. to about 100 psig. for the dispersing gas. Thedispersing gas may also function as at least a portion of the drying gasstream. The various operating parameters noted above may besystematically varied in order to achieve the desired particle size. Forexample, in order to minimize contact between the chamber walls and wetmaterial, the chamber downstream from the nozzle system can be madelarge in size, e.g., from about 4 to about 30 feet in diameter and fromabout 7 to about 30 feet long, often with an additional conical shapedportion for convenient withdrawal of the spray dried material. The spraydrying apparatus may also include separation means, e.g., cycloneseparators in the outlet gas line to recover at least a portion of thematerial entrained in this stream.

One particularly useful variation on the idea of adjustment of thesolids content of the clay slurry fed to the spray dryer might includethe use of additional amounts of a liquid medium (or media), added tothe liquid medium (or media) originally present in the clay slurry. Forexample, many commercially available clay slurries are comprised of 70%clay and 30% water. In some of the more preferred versions of thisprocess, the clay concentration is lowered to about a 40% clayconcentration before the phosphate-containing compound is introducedinto the clay slurry. It also should be noted that the herein describedweight proportions for the liquid media do not count any additionalliquid ingredients such as thickening agents, if such additional liquidagents are in fact present in the total slurry. The presence andproportions of such preferred, but non-essential, ingredients, e.g., gasevolution promoters and/or viscosity agents such as starch, STEREOTEX®,gum arabic, etc.--if used--should not constitute more than about 10% byweight of the total slurry. Such optional ingredients also may includerelatively small amounts of certain other optional or "adjunct"materials. For example, "weighing agents" may be used in the practice ofthis invention in order to impart certain density characteristics to theresulting particles. That is to say that such materials may be employedmore for their effect on the density of the resulting material than fortheir binding capabilities and/or their catalytic activities.

Some other preferred variations of applicant's fundamental process mayinvolve the use of various techniques to aid in the "freezing" of theingredients otherwise accomplished by applicant's spray drying step.Such auxiliary techniques for aiding this "freezing" might include: (1)use of organic thickening agents, (2) use of nonorganic thickeningagents such as alumina, (3) adjustment of the solids content of the clayslurry fed to the spray dryer and/or (4) aging of the clay/phosphatereaction mixtures before carrying out the spray drying step.

Other objects and/or advantages to applicant's process and bindermaterials will be made more apparent from the following drawings anddetailed descriptions regarding the experimental programs used toestablish the scope of applicant's invention.

DESCRIPTION OF THE DRAWINGS

FIG. 1 graphs an attrition index versus the weight percent of phosphatefor a "composite" of several curves having very similar features. Thatis to say this curve is a kind of "average" curve for severalrepresentative systems. The systems depicted were clay-phosphoric acidbinder systems which did not include active catalyst particles as a partof their makeup. The attrition-resistance in both FIGS. 1 and 2 wasmeasured according to the method proposed in ASTM test D-32.02.06, Draft5a, which hereinafter more fully described. In the attrition scaledepicted in the ordinate, a reading of more than about 7 should beconsidered as unacceptably "soft."

FIG. 2 graphs the same attrition index versus the weight of phosphatefor another "composite" curved derived from several representativecurves having similar features. However, FIG. 2 is a composite of agroup of curves representing systems having a representative catalyst(e.g., ZSM-5) as a part of the overall particle. Here again, none of thebinder systems which generated this "composite" curve had an auxiliarybinder ingredient.

Generally speaking, both FIGS. 1 and 2 indicates that: (1) phosphateconcentration levels of less than about 2 percent by weight of thecatalyst-containing binder do not produce acceptableattrition-resistance levels, (2) phosphate concentrations between about6 and 12% are preferred and (3) phosphate concentrations above about 12%and certainly after about 20% again provide only marginal improvementsin attrition-resistance. FIGS. 1 and 2 also tend to suggest that thelower end (2%) of this scale is technical in nature while the upper end(20%) is as much an economic constraint as it is a technical limitationfor catalyst particle container materials.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As was previously noted, applicant believes that the "acid reaction"versions of the herein described processes involve an adjustment of thepH of the slurry (e.g., to a pH level of from about 1.0 to about 3.0) sothat the aluminum components of a given clay lattice will no longer becovalently bonded to oxygen, but rather will be converted, in the acidenvironment, to a cationic condition (e.g., Al⁺⁺⁺) that encouragesbonding of the aluminum to the phosphate oxygen, and thereby creatingthe desired ammonium aluminum phosphate complex units which areparticularly well suited to subsequent vitrification steps. In effect,the acidification step tends to put positive charge on the amphotericaluminum components of the clay.

However, applicant also has established that if the clay is exposed toextremely alkaline conditions (e.g., pH levels of from 10.0 to 14.0) theresulting particles also will posses; the desired attrition-resistantqualities. This ability also follows from the amphoteric nature ofalumina in such clays. Thus it would appear that applicant's acidicpreparation step puts positive charges on the clay while the alkalinepreparation step puts negative charges on the clay. That is to say thatthe experimental evidence all points to the fact that either of thesetechniques will produce the desired results so long as the pH producedby it is "extreme" (e.g., 1.0 to 3.0 or 10.0 to 14.0). Again, however,the "acid reaction" versions of applicant's processes are preferred.That is to say that the need for creation of the "extreme" acidicconditions (e.g., creation of a pH of from about 1.0 to about 3.0) aswell as the "extreme" alkaline conditions (e.g., creation of pH levelsfrom about 14.0 to about 10.0) in the clay slurry have been verified byapplicant's experimentation program even though the theoretical basisfor the alkaline reaction versions of applicant's processes are not aswell understood. In any case, applicant has found that creation ofeither of these extreme pH conditions will serve to produce morefavorable reactions between a clay and a phosphate compound which issubsequently introduced into the herein described clay slurries. Indeed,applicant's experimental program has clearly established that if theseextreme pH conditions are not created in the slurry before the phosphateis introduced into said slurry, the resulting clay/phosphate orclay/phosphate/catalyst particles will have rather poor attritionresistance qualities.

For example, applicant has found that if a slurry is simply initiallycreated to have a middle pH value of from about 6.0 to 8.0--i.e.,without first experiencing either of the "extreme" pH conditionsrequired by applicant's process--then the resulting particles will haverather poor attrition-resistance qualities. However, applicant'sexperimental program also clearly established that when catalyticparticles are used, they should not be introduced into either anextremely acidic (1.0-3.0) or an extremely basic (14.0-10.0 but rathershould be introduced after the slurry is brought to some middle range pHvalue (e.g., 4.0 to 8.0). It also bears repeating that if a given binderformulation is to contain no catalyst component, it is not necessary toraise (or lower) the pH to a 4.0 to 8.0 pH level by the introduction ofphosphate-containing compound(s) such as ammonium phosphate, phosphoricacid etc. Applicant's experimental work also established that therequired phosphate content (e.g., 2 to 20 percent, or 0.25 to about 20.0percent when an auxiliary binder is used) can be introduced into theclay slurry without taking it out of its initial 1.0 to 3.0 pH level. Inthe same vein, an alkaline system need not be taken from its initial14.0-10.0 pH level if no catalyst is to be introduced into applicant'salkaline reaction systems.

Applicant's experimental program also established that a phosphatecomponent constituting even as little as 0.25 percent of the end productparticles is necessary to the successful practice of all of the hereindescribed processes. Applicant verified this point by replacing aphosphate-providing phosphoric acid ingredient, which alone providedeven this small amount of phosphate, with several other kinds of acid.That is to say that applicant tried numerous acids (other thanphosphoric) e.g., formic, acetic, hydrochloric and nitric acid inattempts to produce attrition-resistant binders having no phosphatecomponent whatsoever. In all such cases the end results were identical.There was an immediate increase in the viscosity of the clayslurry--just as there is when the phosphoric acid was used--however,upon spray drying and calcination, the resulting end product particlescompletely disintegrated during attrition testing. From these resultsapplicant has theorized that the attrition-resistant qualities of theherein described matrices is at least in part a result of the formationof a thermally stable, phosphate bond (i.e., this bond withstands thehigh temperatures associated with applicant's calcination step) betweenthe individual clay particles and the phosphate component of thephosphate-containing compound(s).

The experimental evidence also indicated that yet another end result ofusing all three of applicant's process steps is the creation ofparticles which are "encased" in a hard, resilient shell of a vitreousmaterial. That is to say that it appears that these particles have avitreous shell--as opposed to being vitreous throughout. Indeed, theexperimental evidence all points to a need for the conjunctive orcombined use of applicant's ingredient proportions, pH conditions andcalcination parameters in order to create a species of "glass" out ofthe clay and phosphate ingredients. Moreover, it appears that this glassformation is in addition to any chemical reactions which form thethermally stable phosphate/clay chemical bond noted above. In otherwords, if all of applicant's steps are not followed, this "glass" orvitreous shell either does not ultimately form around outside of thebinder particle or the binder/catalyst particle; or if a physical (thatis, temperature induced) "glassing" of these materials does take place,it produces a glass encasement around the particle which is decidedlyinferior with respect to attrition-resistance when compared to thoseparticles produced when all of applicant's process steps are followed.Thus, it appears that not only does applicant's calcination step serveto drive off all volatile matter from the subject particles, it alsoserves to provide the heat conditions which also are necessary to bringabout a "glass forming reaction" between the clay and phosphatemolecules, especially near the surface of the particles and this servesto impart an unusually "tough", attrition-resistant quality to theoutside surface of those particles.

Applicant's experimental work also suggested that the other "physical"steps, e.g., spray drying, extruding and desiccation are less criticalto the overall success of this invention compared to the calcinationstep. However, the details of these other physical steps cannot becompletely disregarded. For example, applicant's spray drying step canbe replaced by other drying and forming procedures known to the catalystproduction arts (e.g., extrusion procedures) which tend to produce muchlarger catalyst units (e.g., those sized on the order of about oneinch). Again, these larger particles are not well suited for use in"fluid" catalytic system; but, they are very useful when employed instationary catalyst "beds."

Applicant's overall experimental program also clearly established thatin order to obtain good attrition-resistance in the herein disclosedbinder matrices or binder/catalyst matrices, it is extremely importantto either have a high enough proportion of phosphate-to-clay (2-20percent phosphate) or to at least augment a low proportion of phosphate(e.g., one providing less than about 2 weight percent to the end productparticles) with an auxiliary binder material such as the glue typebinder materials previously described. In all cases some phosphate mustbe present. The minimal requirement is at about 0.25 percent of theweight of the end product particles. That is to say that applicant'sexperimental work has established that these two "threshold" proportionsof phosphate is indeed mandatory for the production of"attrition-resistance" in the binder systems or in binder/catalystsystems which employ naturally occurring clays in proportions greaterthan about 20 percent.

Applicant's experimental work also established that, in most cases thephosphate component, and especially that provided in percentages lessthan 2.0 percent of the overall material, is most preferably, at leastpartially, provided by phosphoric acid. Indeed, as was previouslydiscussed, because the "0.25 weight percent" phosphate requirementseemed to be so very small, applicant conducted an extensive series oftests which, in effect, tried to substitute various other acids such asformic acid, acetic acid, hydrochloric acid and nitric acid for thisseemingly small percentage of phosphoric acid. Again, the results ofthese tests were consistently bad--that is to say that the particlesresulting from the use of non-phosphate-providing acids had very poorattrition-resistance qualities.

Other experimental work determined the extent of the various pH rangeswhich can be used and still obtain good attrition-resistant catalyst. Atthis point it also might be noted that in the initial stages of theexperimental program, applicant posed the hypothesis that if one carriedout any "gel reactions" in strongly acidic conditions the results wouldbe poor because virtually all known prior art attempts to produce bindermaterials by "gel reactions" carried out at strongly acidic pH levelshad failed. Applicant then obtained a great deal of experimental datathat showed that the introduction of phosphate compounds into a clayslurry at about 5 to 7 pH levels resulted in poor attrition-resistanceof the resulting spray dried particles. This fact seemed to beanomalous. Later experimental work indicated that if applicant startedwith a clay slurry having a low pH (e.g., one created by adding an acidto the slurry) and then added a phosphate-containing compound such asdibasic ammonium phosphate to raise the pH, then binders having highlevels of attrition-resistance could be obtained over a very wide pHrange. This group of experiments also established that applicant's "gelreaction" were not the same kind of "gel reaction" used in the prior artsince they could in fact be carried in acidic conditions which weregenerally regarded as "anathema" to carrying out most prior art "gelreactions."

In another important group of experiments, applicant added a smallamount of phosphoric acid to various clay slurries. This lowered theirpH to less than about 2.0. However, it turned out that there was notenough phosphate to meet the subsequently disclosed "minimumrequirement" (2-20 percent) of phosphate-to-clay needed to produceattrition-resistant matrices. In a later set of experiments, additionalphosphate was supplied by a dibasic ammonium phosphate in order to"adjust the final pH" of the clay slurries. Thus, it was during suchattempts to "adjust the pH" that applicant discovered the 2 percentthreshold requirements for phosphate in the end products. Thereafter,applicant found that with a little trial and error one could findexactly the "right" amount of acid to add initially, in order that theamount of ammonium phosphate subsequently added will give anypredetermined pH with any given amount of phosphate-to-clay. Thereafter,applicant concluded that a bonding effect between the phosphate and theclay was due to the development of a strong charge at the edge of theclay particles.

With this "strong charge" theory in mind, applicant thereafter developedthe "alkaline reaction versions" of these processes by using a strongbase such as ammonium hydroxide to achieve a high pH level (i.e., 14.0to 10.0) before adding phosphoric acid (or other mineral acids) andvarious phosphates such as monobasic ammonium phosphate in order toadjust the pH downward to various lower values (e.g., to pH levels offrom 4.0 to 8.0). It also turned out that even organic acids could beused for this pH lowering purpose. It also should be noted in passingthat when this alkaline reaction technique was employed, applicant foundthat he did not have to pay quite as "strict" attention to the order ofaddition of the various components as in the "acid reaction" versions ofthe process. That is to say that in these "alkaline reaction" versionsthere are many cases where the phosphate-containing compound (e.g.,monobasic and dibasic ammonium phosphates) and an acid such asphosphoric acid can be added simultaneously without adversely affectingthe attrition-resistance of the resulting particles.

Another area investigated by applicant revolved around the question asto why applicant obtained such large improvements in the activity of thevarious zeolites used in the various clay matrices. A brief review ofthis line of experiments would probably be helpful to a better overallunderstanding of the scope of this invention. In one series ofexperiments, applicant worked with several zeolites, but particularlyZSM-5, in various prior art silica-alumina binder systems. The resultsthereof were compared to analogous zeolites bound in applicant's bindersystems. The results were dramatic--four-fold improvements in activitywere often obtained. These results became even more dramatic when it wasdetermined that many of applicant's matrices had pH values of about 2.0.Applicant tried several experimental approaches to link the improvementin catalytic activity solely to the low pH of the clay matrix. Theseexperiments were unsuccessful. Indeed, subsequent experimentsestablished that even better activities were obtained if a matrix had ahigher pH. Applicant also found that other zeolites totally unrelated toZSM-5 responded in much the same way. Indeed, it later turned out thatwidely varying types of catalysts could be so employed without sufferingcatalytic activity losses.

An extended experimental program was then directed at trying tounderstand what all zeolites have in common which made applicant'sclay/phosphate matrices interact so favorably with them. To this end,applicant centered a group of experiments around an initial propositionthat if a catalyst has a higher activity in a different binder, thenthat higher activity must be du to one of several factors (or somecombination of those factors). For example, applicant explored, byexperimental procedures, the proposition that a given matrix may simplyprovide an environment in which a catalyst particle, e.g., zeolite ismore chemically stable. That is to say that applicant conducted variousexperiments which sought to reduce the chemical interaction betweenapplicant's clay and phosphate components and various zeolite catalystmaterials. Applicant also explored the proposition that the reactantsare simply more accessible to a catalyst such as a zeolite in one matrixthan in another.

In considering these questions, applicant repeatedly observed that allof the active catalyst particles investigated had well defined portopenings and were otherwise such that the reactant molecules coulddiffuse through to reach the active surface of the catalyst. Therefore,the external surface of the catalyst (e.g., a zeolite) and itsavailability in the matrix were considered to be of extreme importancein determining the activity of a particular catalyst. If part of thesurface were blocked in any fashion then there seemed to be an almostproportional loss in activity of the catalyst.

It is with this idea in mind that applicant developed an explanation forthe improvements in activity that were observed which seems to beconsistent with all of the experimental evidence. This explanation iscentered around the idea that the subject zeolite catalyst systems havecertain factors in common. For example, zeolite crystals are typicallygrown to a size of about 0.5 microns. However, one never obtains singlecrystals. Usually zeolites are agglomerated in rather haphazard ways andin the prior art procedures for processing said zeolites, theagglomerates can grow to an average size of 30 microns. In order tovisualize these agglomerates one must view the individual crystals assmall blocks that are randomly stacked on top of one another so thatlarger particles are formed. When one crystal lays on top of another theports that lead into the interior surface of the zeolite are blocked andthere is a concomitant loss of catalytic activity. Moreover, applicant'sexperimental evidence suggested that there was nothing that applicant'sclay matrix systems could do to retrieve this loss.

There is, however, another source of blockage that applicant'sparticular matrices did alleviate. This form of alleviation seems to berelated to the fact that the agglomerated particles of zeolite are notsimply solid masses of crystals packed tightly together. Indeed, theyhave pore structures of their own, commonly referred to as a "macropore"systems. Such macropore systems can have openings as large as 1000Angstroms. Applicant's experimental work indicated that theclay/phosphate matrices formed by applicant's processes cannot enterthese macropores since the individual clay particles are typically ofthe order of 0.25 microns or 2500 Angstroms. Applicant believes thatthis is the primary reason why such a large improvement in catalyticactivity has been maintained in the herein described binder particles.Applicant also believes that these clay/phosphate binders stand apartfrom other binders in that the pH of applicant's systems can becontrolled to any desired value. Thus, applicant's ability to make claybinders having pH levels of from about 1.0 all the way to about 14.0 hasgreat potential value to the catalyst-employing arts.

Moreover, since applicant's binder does not depend on forming a gel froma liquid sol or as a dissolved chemical such as sodium silicate oraluminum sulphate, there is no possibility of blocking the surface portsof the zeolites. These facts are believed to be especially significantwhen they are compared with the fact that most prior art binder systemshave one factor in common. When they are first mixed with a zeolite,they are in the form of a liquid sol or as a dissolved chemical such assodium silicate or aluminum sulfate. The particles in these sols areabout 20 Angstroms in diameter. Hence, they can easily fill themacropores of the zeolite agglomerates. Consequently, when they gel,they tend to block the macropores of the zeolite agglomerates therebyreducing the catalytic activity.

However, the experimental evidence also indicated that the catalyticactivity of certain small particulate catalysts such as ZSM-5 could beimproved by treating these catalyst particles with one of applicant'sphosphate-containing compounds (and especially phosphoric acid). That isto say that zeolites treated in this manner made especially goodcatalysts for use in applicant's binder systems. Indeed, this enhancedactivity was to a large degree maintained in binder systems other thanthose forming the subject matter of this patent disclosure. Therefore,this method (i.e., exposure of catalysts such as zeolites to phosphatecompounds and then using them in non-clay-containing binder systems suchas those found in the prior art) of obtaining increased catalyticactivity may become the subject matter of a later "continuation-in-part"patent application.

However, be that as it may, the subject matter and scope of the instantpatent disclosure will now be further illustrated by the followingdescriptions of procedures and representative experimental tests.

EXPERIMENTAL METHODS AND RESULTS THEREOF Procedures

Certain experimental data demonstrating applicant's overall inventionwill now be summarized. Detailed descriptions of certain specificexperiments which provided the data will then be given as examples ofthe overall processes described herein. To this end, it first should benoted that one widely used "standard" procedure used for preparingapplicant's binder systems generally was to add water to a clay slurryand then adjust the clay content thereof to about 40% weight. That is tosay that the clays initially employed often contained 70% weight clayand that these were diluted to about a 40% clay concentration with anappropriate liquid media such as water. After the slurry was placedunder "extreme" pH conditions, a phosphate compound was added to theslurry, usually under vigorous stirring conditions. The clays, catalystsand phosphates most widely used in applicant's experimental programswere:

    ______________________________________                                        RAW MATERIALS                                                                 TYPE          SOURCE       GRADE                                              ______________________________________                                        CLAYS                                                                         Kaolin Clay   Thiele       Grade RC-32                                        Kaolin Clay   Georgia Kaolin                                                                             Wrens Clay                                                                    Slurry                                             Kaolin Clay   Thiele       Low Soda Slurry                                    CATALYSTS                                                                     ZSM-5         Mobil        Mobil No. 1                                        ZSM-5         Mobil        ROF                                                REY Zeolite   Conteka      CBV-400                                            USY Zeolite   PQ           30-063                                             PHOSPHATES                                                                    Phosphoric Acid            85% H.sub.3 PO.sub.4                               Monobasic Ammonium         100% (NH.sub.4) H.sub.2 PO.sub.4                   Phosphate                                                                     Dibasic Ammonium           100% (NH.sub.4).sub.2 HPO.sub.4                    Phosphate                                                                     ______________________________________                                    

Spray Dryer

The spray dryer pump discharge pressures were typically 10-15 PSIG withdead-head pressures in excess of 40 PSIG. Slurries that could be forcedinto pump suction under such conditions could be conveniently pumpedinto a dryer.

ATTRITION TEST AND CATALYTIC ACTIVITY

The products of applicant's experimental program were tested by variousphysical and chemical tests. Two of the most important of these were anattrition measuring test and a catalyst activity measuring test. A briefdescription of these tests, especially with respect to some particularlyimportant catalyst types will be given by way of example.

The various samples were tested for their resistance to attrition usinga proposed ASTM standard test method (ASTM D-32.02.06, Draft Number 5a)for determining the attrition and abrasion resistance of powderedcatalysts by air jets. This method is still under evaluation by an ASTMstandards committee and has not been accorded the status of an ASTM TestMethod. Each test was run on 50 grams of humidified sample. The sampleswere placed in an attriting tube and run for one hour. At the end ofthis period the amount of fines collected in a fines collection assemblywas determined. The sample was then attrited for an additional hour. Atthe end of this time the fines in the collection assembly weredetermined. An "Attrition Index" of the sample was determined as thetotal fines made less the fines made in the first hour divided by thetotal weight of the sample less the fines made in the first hour timesone hundred. In this particular test, applicant regarded an attritionindex of less than seven as being an acceptable material. An index ofless than one is indicative of a truly excellent material.

Catalytic Activity Test

The catalytic activities of various catalyst samples were determined byASTM Method No. 3907 - 87. The apparatus and operating procedures inthis test method were followed in testing the catalysts preparedaccording to the teachings of this application; however, the operatingconditions of the test were modified for the particular type of catalystbeing evaluated. These tests were particularly concerned with evaluatingtwo general types of catalyst. The first type were those additives thatare combined with other catalysts; typical of these are the ZSM-5containing catalysts. The second type of catalysts were the FCCcatalysts; typical of these are the faujasite containing catalysts. Theprocedure for determining the activity of these two types of catalystsare detailed in the following sections.

Additive Type Catalysts

These catalysts were evaluated by first steam deactivating them and thenadding a small quantity, usually 4% by weight, to a standard catalyst.The catalysts were deactivated by flowing a mixture consisting of 55%volume steam and 45% volume air through a bed of catalyst maintained at1450° F. (790° C.) for ten hours. The "standard" catalyst was then runon the microactivity test at the following nominal conditions:

    ______________________________________                                        Temperature            960° F. (515C)                                  WHSV, GMS.OIL/HR., GM CAT                                                                             10.0                                                  TIME, SEC               80.0                                                  GMS. CATALYST           4.0                                                   GMS. OF OIL             0.9                                                   ______________________________________                                    

A complete set of yields was obtained. These included all of the lighthydrocarbons from hydrogen up to and including all of C4 hydrocarbons.To the standard catalyst 4% by weight of the steam deactivated catalystwas added and the test was rerun. The activity of the additive wasdefined as the increase in the volumetric yield of propylene, butyleneand isobutane. Typically, the sum of these products was 20.6% by volumefor the standard catalyst and 27.6% for the standard catalyst with theadditive. Frequently it is necessary to alter the ZSM-5 content of theadditive, or to use more or less additive in the test. In this case theactivity is defined on the basis of 1% weight ZSM-5. In the examplegiven above, if the catalyst contained I2.5% weight ZSM-5 and 4% weightwas mixed with the standard catalyst, the activity would be 14. Thismethod of measuring activity was used with respect to a very widevariety of samples.

Faujasite Catalysts

These catalysts were evaluated for their catalytic activity by firststeam deactivating them. The deactivation procedure employed was to flow100% by volume steam through a bed of the catalyst maintained at 1400°F. (795 ° C.) for four hours. The nominal operating conditions on themicroactivity test were as follows:

    ______________________________________                                        Temperature            960° F. (515C)                                  WHSV, GMS.OIL/HR, GM. CAT.                                                                            16.0                                                  TIME, SEC.              80.0                                                  GMS. CATALYST           3.0                                                   GMS. OF OIL             0.9                                                   ______________________________________                                    

The activity of the catalyst is defined as 100 minus the percent volumeof cracked material boiling above 430° F. This material, referred to asthe "cycle oil", is determined by conventional gas--liquidchromatography.

Sample Analysis And Data Treatment

The spray dryer discharge samples were typically calcined at 800°-2,000°F. for from 30 to about 100 minutes. However most of applicant's testswere conducted at 1000° F. for about one hour. Several tests alsoindicated that temperatures of about 1350° F. are highly preferred.Samples of each spray dryer run were sent to an outside commercialanalytical lab for analysis prior to sending them to another outsidefacility for attrition and density testing.

Discussion Of Preferred Materials In View Of Certain SpecificExperimental Results

Various experimental results indicated that particularly good resultswere obtained from the conjunctive use of phosphoric acid and one ormore other phosphate-containing compounds. For example, in carrying outthe experiment described in example 1, phosphoric acid (H3PO4) was addedto a dilute (40%) clay slurry and the particulate material that resultedfrom spray-drying and calcination had an attrition index of 1.0. The pHof the clay slurry, after adding the phosphoric acid, was 1.7. The nextstep in this particular experiment employed mono-basic ammoniumphosphate. The formula for this compound is (NH4)H2PO4; hence oneammonia group has reacted with a hydrogen ion in the acid. In thisparticular experiment the pH of the resulting slurry was 4.3. Theattrition-resistance of the resulting particles was 1.8.

An analogous experiment was made using dibasic ammonium phosphate. ThepH of the slurry was 7.7. The attrition resistance of the resultingparticles was 1.2. Applicant also did some experiments where the pH ofthe slurry was adjusted to between 6 and 7 pH by using various mixturesof the above compounds to obtain various pH's. Applicant found that inthis range of pH's the resulting particles generally had rather poorresistance to attrition. The results of these experiments are summarizedin Table 1.

                  TABLE 1                                                         ______________________________________                                                                    ATTRI-                                            EXAMPLE  TYPE PO4     pH    TION   COMMENTS                                   ______________________________________                                        1        ACID         1.7   1                                                 2        MONO         4.3   1.8                                               3        Dl           7.7   1.2                                               4        DI + ACID    7     19.2   INIT. pH--7.8                              5        MONO + BASE  7     8.4    INIT. pH--6.3                              6        DI + ACID    6.5   12.8   INIT. pH--7.3                              ______________________________________                                    

These results are consistent with the observation that the edge surfaceof kaolinites clays are at there isoelectric point at about pH 7.0. Atlow pH they may acquire a positive charge and at high pH they mayacquire a negative charge. In general, this group of experiments showedthat particles with very high attrition-resistance can be made if theclay slurry is initially brought to a low or a high pH. Applicantsubsequently found that particles with good attrition-resistance couldbe made as long as the clay slurry was first brought to a low or a highpH and then adjusted to any intermediate pH. The significant pointcoming out of this work experimental was that applicant's process givesan ability to use clay, an inert material from a catalytic viewpoint,and use it to great economical advantage in preparing a wide variety ofmaterials useful in the catalytic arts. In addition, applicantsprocesses have the added advantage of giving an ability to control thepH of the media into which the various catalytic components are blended.The advantages of this will be demonstrated in subsequent examples.

After determining the effect of pH on the attrition-resistance of theclay-phosphate particles, applicant then directed his attention to theeffect of the amount of phosphate used in the clay. One series ofexperiments was made with clay and phosphoric acid as the phosphatesource. The results of the experiments are summarized in Table 2.

                  TABLE 2                                                         ______________________________________                                        EXAMPLE  TYPE PO4   PO4, % WT  pH   ATTRITION                                 ______________________________________                                        1        ACID       9.8        1.7  1.0                                       7        ACID       6.5        2.1  17.0                                      8        ACID       3.2        2.7  3.3                                       ______________________________________                                    

These results were "anomalous" in that they show that at about 6.5%weight phosphate the particles demonstrate greatly reduced resistance toattrition. Applicant has observed similar behavior with otherexperimental preparations at this phosphate concentration. It istheorized that these results show that there are critical concentrationsof phosphate in the clay slurry where the phosphate reacts entirely withthe clay surface of a single particle and fails to form cross links withadjacent clay particles. The result is that while individual clayparticles form a tough vitreous shell they fail to form a bond betweenparticles and the final aggregate has no attrition resistance. Thesignificance of these results is that various clays, depending on theirsource, may behave somewhat differently from some other clay used. Thatis to say that the point of minimum attrition cannot always be preciselydefined. Applicant normally used clays from East Georgia and theserepresent some of the largest clay deposits in North America; however asexperience was gained with other kaolinites it became evident thatsomewhat different results will be obtained with the use of differentsources of "the same" clay. These data reinforce the idea that we aredealing with naturally-occurring minerals and not precise chemicalcompounds; and, as a result some variation is to be expected fromdifferent clay sources.

Preparation Of Certain Catalyst Matrices

Many commercially available catalysts are comprised of four maincomponents; a faujasite or some other active catalytic material, anamorphous component, a binder material or glue and a filler clay. Thebinder, the amorphous component and the filler clay are frequentlyreferred to as the matrix of the catalyst. This usage is sometimesemployed in this patent application as well.

In any event, in the following examples, applicant will detail certainexperimental work which was concerned with using representative bindersystems to prepare various catalyst matrices of particular commercialinterest. As noted previously these active matrices may in fact act ascatalysts in their own right and may indeed be utilized as such. Forexample one set of experiments considered the use of gel alumina as theamorphous material in a role as a catalyst material. In this particularapplication the gel alumina could also be considered as an "auxiliarybinder." The experimental procedure for preparing the resulting matrixis detailed in Example 9. It shows that the ratio of clay binder to gelalumina was 2-to-1 and that the alumina was dispersed with 0.6milliequivalent of acetic acid. Dibasic ammonium phosphate was used asthe phosphate source. The pH of the clay alumina slurry was 7.3. Amatrix with an attrition-resistance of 3.8 was obtained.

By way of further example of the use of amorphous materials werecombinations of gel alumina and activated alumina. For example, inExample 8 the composition was 50% clay binder and 50% amorphousmaterial. The amorphous material, in turn, was 50% gel alumina and 50%activated alumina. When dibasic ammonium phosphate was used as thephosphate source a resulting material with an attrition index of 0.8 wasobtained. In Example 11 applicant altered the ratio of binder toamorphous material by lowering the amount of gel alumina from 25% to15%. In this example, monobasic ammonium phosphate was used as thephosphate source; the pH was 6.1 and the attrition-resistance was 1.6.Example 12 was similar to Example 8 except that a mixture of phosphoricacid and monobasic ammonium phosphate was used; the pH was 3.5. Theattrition resistance of the matrix was 0.37.

Preparation of Synthetic Zeolites

As was previously noted, synthetic zeolites comprise a large group ofcatalytic materials of great interest to commercial operations. The mostimportant zeolite in this group is ZSM-5. In formulating this zeoliteinto a useful particle it is only necessary to use a clay binder; thatis to say that other catalytic components such as amorphous catalystsare not necessary. Examples 13 and 14 describe the preparation of atypical ZSM-5 catalyst using phosphoric acid (Example 14) and dibasicammonium phosphate (Example 13). Both phosphates result in particleswith excellent attrition resistance. However, there are significantdifferences in the activity of the finished catalysts. This differencein activity demonstrates another significant advantage of applicant'sclay-phosphate binder formulation; this is the ability to control the pHof the binder slurry. In Example 14 the pH of the clay--binder--zeoliteslurry was 4.0. The activity index of the finished catalyst was 12.7.

In Example 13 the pH of the slurry was 8.0 and the activity of thecatalyst was 23.8. This is approximately a two-fold improvement inactivity. Applicant believes that at the lower pH some alumina isremoved from the structure of the zeolite and this results in lowercatalytic activity of the zeolite. However, it also should be noted inpassing that the ability of the clay-phosphate binder to provideeffective binding at high pH's is a very significant advantage; it alsoshould be noted that all existing commercial binders are only effectiveat lower pH values of about 2.5 to 4.0.

Example 15 demonstrates the preferred method of preparing the ZSM-5catalyst. The clay is first brought to a low pH with phosphoric acid andthen the pH of the clay slurry is adjusted to 7.3 with dibasic ammoniumphosphate; the ZSM-5 zeolite is added at this point. The activity andattrition results with this method are similar to those obtained inExample 13. The critical point is that the ZSM-5 zeolite not contact thelow pH (<4.0) clay--phosphate slurry.

Preparation Of Faujasite Catalysts

The faujasite group of zeolites are by far the most important catalystsin petroleum cracking operations. In such operations, zeolites aregenerally combined with one or more amorphous catalysts in the sameparticle. In some of applicant's experiments, applicant chose a gelalumina

as the amorphous component and rare earth exchanged Y (REY) as thefaujasite. The details of such a preparation are given in Example 16.The phosphate source was dibasic ammonium phosphate and the gel aluminawas prepared by dispersing it in 0.5 milliequivalent of nitric acid pergram of alumina. The pH of the final slurry was 6.9. the activity of thefinished catalyst was 77.3. Example 17 gives the details of apreparation in which phosphoric acid was used as phosphate source. Thelow pH of the clay-phosphate slurry caused extensive damage to the REYzeolite and the resulting activity was 15.8. This low activity indicatesalmost total destruction of the zeolite. However it also should be notedthat there are many zeolites in the faujasite group that will beunaffected by the pH of the binder. It also should be pointed out thattypical zeolite would be the ultra stable Y zeolites (USY). The reasonfor this is that the zeolites have been dealuminated by high temperaturesteaming and controlled acid leaching. After their preparation many ofthese zeolites are stable to boiling mineral acids. Example 18 gives thedetails of a preparation of a USY catalyst.

Applicant has theorized that one of the major factor that accounts forthe large improvements in the activity of the catalysts made with theclay-phosphate matrix is that there is no liquid sol to fill themacropores of the zeolite particles. This makes more of the surfaceports of the zeolite crystals accessible to reactants. To demonstratethis point applicant prepared a common type of commercially availableFCC catalyst using a conventional binder. The details of thispreparation are given in Example 19. The binder was a gel aluminapeptized with formic acid; the faujasite was a mixture of Y zeolite andcomprised 25% weight of the catalyst. A filler clay was used and thiscomprised 50% of the catalyst. The attrition resistance of the catalystwas 7.0; the activity was 80.

Example 20 gives the details of making a similar catalyst using aclay-phosphate binder. The faujasite components were the same as inExample 16. An activated alumina was substituted for the alumina gel.The matrix was prepared by using dibasic ammonium phosphate with theclay. The finished catalyst had an attrition index of 0.8; a verysignificant improvement over the conventional catalyst. The activity was85 which is also a very large improvement in activity.

SELECT EXPERIMENTS Example 1

This example describes the preparation of a clay-phosphate binder usingphosphoric acid as the phosphate source. In this preparation 1436 gramsof a 70% weight kaolin clay slurry were diluted to 40% weight by adding947 milliliters of water. The resulting mixture was stirred at highspeed in a Waring blender. The 70% clay slurry is a commercial gradematerial designated as Thiele Grade RC-32. To the diluted slurry, 117grams of phosphoric acid of 85% concentration was added while continuingto mix at a high speed. The pH of the slurry was 1.7. There was animmediate increase in the viscosity of the slurry. The slurry was spraydried to produce a particle with an average size of 65 microns. Thespray-dried product was calcined in air for one hour at 1000° F. Thecalcined particles were then tested for their resistance to attritionand found to have an attrition index of 1.0.

Example 2

This example describes the preparation of a clay-phosphate binder usingmonobasic ammonium phosphate as the phosphate source. In thispreparation 1681 grams of a 70% weight kaolin clay slurry were dilutedto 40% weight by adding 1176 milliliters of water. The resulting mixturewas stirred at high speed in a Waring blender. The 70% clay slurry is acommercial grade material designated as Thiele Grade RC-32. To thediluted slurry, 29.4 grams of monobasic ammonium phosphate dissolved in100 milliliters of water was added while continuing to mix at a highspeed. The pH of the slurry was 4.3. There was an immediate increase inthe viscosity of the slurry. The slurry was spray dried to produce aparticle with an average size of 65 microns. The spray dried product wascalcined in air for one hour at 1000° F. The calcined particles werethen tested for their resistance to attrition and found to have anattrition index of 1.8.

Example 3

This example describes the preparation of a clay-phosphate binder usingdibasic ammonium phosphate as the phosphate source. In this preparation1681 grams of a 70% weight kaolin clay slurry were diluted to 40% weightby adding 1176 milliliters of water. The resulting mixture was stirredat high speed in a Waring blender. The 70% clay slurry is a commercialgrade material designated as Thiele Grade RC-32. To the diluted slurry,35 grams of dibasic ammonium phosphate dissolved in 100 milliliters ofwater was added while continuing to mix at a high speed. The pH of theslurry was 7.7. There was an immediate increase in the viscosity of theslurry. The slurry was spray dried to produce a particle with an averagesize of 65 microns. The spray dried product was calcined in air for onehour at 1000° F. The calcined particles were then tested for theirresistance to attrition and found to have an attrition index of 1.2.

Example 4

This example describes the preparation of a clay-phosphate binder usingdibasic ammonium phosphate plus phosphoric acid as the phosphate source.In this preparation 1637 grams of a 70% weight kaolin clay slurry werediluted to 40% weight by adding 727 milliliters of water. The resultingmixture was stirred at high speed in a Waring blender. The 70% clayslurry is a commercial grade material designated as Thiele Grade RC-32.To the diluted slurry, 34 grams of dibasic ammonium phosphate in a 25%weight solution in water was added while continuing to mix at a highspeed. There was an immediate increase in the viscosity of the slurry.The pH of the slurry was 7.8. To this mixture, 11.2 grams of 85%phosphoric acid was added. The pH dropped to 7.0. It was necessary toadd an additional 550 milliliters of water to the slurry to reduce theviscosity. The slurry was spray dried to produce a particle with anaverage size of 65 microns. The spray dried product was calcined in airfor one hour at 1000° F. The calcined particles were then tested fortheir resistance to attrition and found to have an attrition index of19.2.

Example 5

This example describes the preparation of a clay-phosphate binder usingmonobasic ammonium phosphate as the phosphate source. In thispreparation 1639 grams of a 70% weight kaolin clay slurry were dilutedto 40% weight by adding 717 milliliters of water. The resulting mixturewas stirred at high speed in a Waring blender. The 70% clay slurry is acommercial grade material designated as Thiele Grade RC-32. To thediluted slurry, 34 gams of monobasic ammonium phosphate in a 25% weightsolution in water was added while continuing to mix at a high speed.There was an immediate increase in the viscosity of the slurry. The pHof the slurry was 6.3. To this mixture 18 milliliters of concentratedammonium hydroxide were added. The pH increased to 7.0. The slurry wasspray dried to produce a particle with an average size of 65 microns.The spray dried product was calcined in air for one hour at 1000° F. Thecalcined particles were then tested for their resistance to attritionand found to have an attrition index of 8.4.

Example 6

This example describes the preparation of a clay-phosphate binder usingdibasic ammonium phosphate plus phosphoric acid as the phosphate source.In this preparation 1637 grams of a 70% weight kaolin clay slurry werediluted to 40% weight by adding 727 milliliters of water. The resultingmixture was stirred at high speed in a Waring blender. The 70% clayslurry is a commercial grade material designated as Thiele Grade RC-32.To the diluted slurry, 34 grams of dibasic ammonium phosphate in a 25%weight solution in water was added while continuing to mix at a highspeed. There was an immediate increase in the viscosity of the slurry.The pH of the slurry was 7.3. To this mixture 23.6 grams of 85%phosphoric acid were added. The pH dropped to 6.5. The slurry was spraydried to produce a particle with an average size of 65 microns. Thespray dried product was calcined in air for one hour at 1000° F. Thecalcined particles were then tested for their resistance to attritionand found to have an attrition index of 12.8.

Example 7

This example describes the preparation of a clay-phosphate binder usingphosphoric acid as the phosphate source. In this preparation 1550 gramsof a 70% weight kaolin clay slurry were diluted to 40% weight by adding872 milliliters of water. The resulting mixture was stirred at highspeed in a Waring blender. The 70% clay slurry is a commercial gradematerial designated as Thiele Grade RC-32. To the diluted slurry, 78grams of phosphoric acid of 85% concentration was added while continuingto mix at a high speed. The pH of the slurry was 2.1. There was animmediate increase in the viscosity of the slurry. The slurry was spraydried to produce a particle with an average size of 65 microns. Thespray-dried product was calcined in air for one hour at 1350° F. Thecalcined particles were then tested for their resistance to attritionand found to have an Attrition Index of 17.

Example 8

This example describes the preparation of a clay-phosphate binder usingphosphoric acid as the phosphate source. In this preparation 1615 gramsof a 70% weight kaolin clay slurry were diluted to 40% weight by adding846 milliliters of water. The resulting mixture was stirred at highspeed in a Waring blender. The 70% clay slurry is a commercial gradematerial designated as Thiele Grade RC-32. To the diluted slurry, 39grams of phosphoric acid of 85% concentration was added while continuingto mix at a high speed. The pH of the slurry was 2.7. There was animmediate increase in the viscosity of the slurry. The slurry was spraydried to produce a particle with an average size of 65 microns. Thespray-dried product was calcined in air for one hour at 1350° F. Thecalcined particles were then tested for their resistance to attritionand found to have an Attrition Index of 3.3.

Example 9

This example describes the preparation of a particle containing anamorphous catalyst formed into an attrition resistant material using aclay-phosphate binder. The amorphous catalyst was a gel alumina obtainedfrom Condea Chemie as is designated Pural SB. It was prepared forinclusion into the binder by dispersing a 26.5% weight alumina slurry inwater in 0.5 milliequivalent of acetic acid per gram of alumina. Theclay binder was prepared by diluting 1121 grams of a 70% weight kaolinclay slurry with 479 milliliters of water in a waring blender. To thediluted clay 31.4 grams of dibasic ammonium phosphate dissolved in 100milliliters of water were added to the clay slurry. There was animmediate increase in the viscosity of the clay slurry. The dispersedalumina slurry was added to the clay slurry plus 500 milliliters ofwater to reduce the viscosity. The pH of the resulting mixture was 7.3.The slurry was spray dried to produce a particle of approximately 65microns. The spray-dried product was calcined in air for one hour at1000° F. The calcined particles were then tested for their resistance toattrition and found to have an Attrition Index of 3.8.

Example 10

This example describes the preparation of a particle containing anamorphous catalyst formed into an attrition resistant material using aclay-phosphate binder. The amorphous catalyst was a combination of a gelalumina and an activated alumina. The gel alumina was obtained fromCondea Chemie as is designated Pural SB; the activated alumina wasobtained from Alcoa chemical company and was designated grade CP 1.5.The gel alumina was prepared for inclusion into the binder by dispersinga 30% weight alumina slurry in water in 0.5 milliequivalent of aceticacid per gram of alumina. The activated alumina was prepared byslurrying 250 grams of it in 464 milliliters of water. The clay binderwas prepared by diluting 840 grams of a 70% weight kaolin clay slurrywith 470 milliliters of water in a Waring blender. To the diluted clay17.5 grams of dibasic ammonium phosphate dissolved in 50 milliliters ofwater were added to the clay slurry. There was an immediate increase inthe viscosity of the clay slurry. The dispersed alumina slurry was addedto the clay slurry, followed by the activated alumina slurry. The pH ofthe resulting mixture was 8.0. The slurry was spray dried to produce aparticle of approximately 65 microns. The spray-dried product wascalcined in air for one hour at 1000° F. The calcined particles werethen tested for their resistance to attrition and found to have anAttrition Index of 0.8.

Example 11

This example describes the preparation of a particle containing anamorphous catalyst formed into an attrition resistant material using aclay-phosphate binder. The amorphous catalyst was a combination of a gelalumina and an activated alumina. The gel alumina was obtained fromCondea Chemie as is designated Pural SB; the activated alumina wasobtained from Alcoa chemical company and was designated grade CP 1.5.The gel alumina was prepared for inclusion into the binder by dispersinga 20% weight alumina slurry in water in 0.5 milliequivalent of nitricacid per gram of alumina. The activated alumina was prepared byslurrying 250 grams of it in 464 milliliters of water. The clay binderwas prepared by diluting 1008 grams of a 70% weight kaolin clay slurrywith 1507 milliliters of water in a Waring blender. To the diluted clay96 grams of monobasic ammonium phosphate dissolved in 150 milliliters ofwater were added to the clay slurry. There was an immediate increase inthe viscosity of the clay slurry. The dispersed alumina slurry was addedto the clay slurry, followed by the activated alumina slurry. The pH ofthe resulting mixture was 6.1. The slurry was spray dried to produce aparticle of approximately 65 microns. The spray-dried product wascalcined in air for one hour at 1000° F. The calcined particles werethen tested for their resistance to attrition and found to have anAttrition Index of 1.6.

Example 12

This example describes the preparation of a particle containing anamorphous catalyst formed into an attrition resistant material using aclay-phosphate binder. The amorphous catalyst was a combination of a gelalumina and an activated alumina. The gel alumina was obtained fromCondea Chemie as is designated Pural SB; the activated alumina wasobtained from Alcoa chemical company and was designated grade CP 1.5.The gel alumina was prepared for inclusion into the binder by dispersinga 20% weight alumina slurry in water in 0.5 milliequivalent of nitricacid per gram of alumina. The activated alumina was prepared byslurrying 250 grams of it in 464 milliliters of water. The clay binderwas prepared by diluting 1008 grams of a 70% weight kaolin clay slurrywith 1507 milliliters of water in a Waring blender. To the diluted clay48 grams of monobasic ammonium phosphate dissolved in 100 milliliters ofwater plus 48 grams of 85% phosphoric acid were added to the clayslurry. There was an immediate increase in the viscosity of the clayslurry. The dispersed alumina slurry was added to the clay slurry,followed by the activated alumina slurry. The pH of the resultingmixture was 3.5. The slurry was spray dried to produce a particle ofapproximately 65 microns. The spray-dried product was calcined in airfor one hour at 1000° F. The calcined particles were then tested fortheir resistance to attrition and found to have an Attrition Index of0.37.

Example 13

This example describes the preparation of a particle containing asynthetic zeolitic catalyst formed into an attrition resistant materialusing a clay-phosphate binder. The synthetic zeolite is a ZSM-5 typecatalyst obtained from Mobil Chemical Corporation. The clay binder wasprepared by diluting 1432 grams of a 70% weight kaolin clay slurry with342 milliliters of water in a Waring blender. To the diluted clay 34grams of dibasic ammonium phosphate in a 25% weight water solution wereadded to the clay slurry. There was an immediate increase in theviscosity of the clay slurry. The ZSM-5 zeolite was slurried in water;the solids content of the slurry was 31.6% weight. The pH of theresulting mixture was 6.4. The slurry was spray dried to produce aparticle of approximately 65 microns. The spray dried product wascalcined in air for one hour at 1000° F. The calcined particles werethen tested for their resistance to attrition and found to have anAttrition Index of 1.6. The catalyst was also tested for activity aftersteam deactivation and found to have an Activity Index of 23.8.

Example 14

This example describes the preparation of a particle containing asynthetic zeolitic catalyst formed into an attrition resistant materialusing a clay-phosphate binder. The synthetic zeolite is a ZSM-5 typecatalyst obtained from Mobil Chemical Corporation. The clay binder wasprepared by diluting 1374 grams of a 70% weight kaolin clay slurry with342 milliliters of water in a Waring blender. To the diluted clay 121grams of 85% phosphoric acid were added to the clay slurry. There was animmediate increase in the viscosity of the clay slurry. The ZSM-5zeolite was slurried in water; the solids content of the slurry was18.6% weight. The pH of the resulting mixture was 4.0. The slurry wasspray dried to produce a particle of approximately 65 microns. The spraydried product was calcined in air for one hour at 1000° F. The calcinedparticles were then tested for their resistance to attrition and foundto have an Attrition Index of 1.2. The catalyst was also tested foractivity after steam deactivation and found to have an Activity Index of12.7.

Example 15

This example describes the preparation of a particle containing asynthetic zeolitic catalyst formed into an attrition-resistant materialusing a clay-phosphate binder. The synthetic zeolite is a ZSM-5 typecatalyst obtained from Mobil Chemical Corporation. The clay binder wasprepared by diluting 1586 grams of a 60% weight kaolin slurry with 650milliliters of water in a Waring blender. To the diluted clay 19 gramsof 85% weight phosphoric acid were added. There was an immediateincrease in the viscosity of the slurry and the pH dropped to 2.4. Tothe acidified clay slurry 350 grams of a 40% weight solution of dibasicammonium phosphate was added. The pH increased to 7.42. The ZSM-5zeolite was prepared by slurrying 63 grams in water; the solids contentof the slurry was 26.0% weight. This slurry was added to the clay slurryand mixed in the Waring blender. The pH of the mixture was 7.3. Theslurry was spray dried to produce a particle of approximately 65microns. The spray dried particles were calcined in air for one hour at1350° F. The calcined particles were then tested for their resistance toattrition and found to have an Attrition Index of 4.4. the catalyst wasalso tested for activity after steam deactivation and found to have anActivity Index of 24.

Example 16

This example describes the preparation of a particle containing afaujasite catalyst combined with an amorphous catalyst and formed intoan attrition resistant material using a clay-phosphate binder. Theamorphous catalyst was a gel alumina obtained from Condea Chemie anddesignated Pural SB. The alumina was prepared for inclusion into thebinder by dispersing a 20% weight alumina slurry in water in 0.5milliequivalent of nitric acid per gram of alumina. The clay binder wasprepared by diluting 1146 grams of a 70% weight kaolin clay slurry with736 milliliters of water; 200 grams of REY zeolite was added to the clayslurry and mixed at high speed in a Waring blender. To the clay-REYslurry, 24 grams of dibasic ammonium phosphate dissolved in 75milliliters of water were added. There was an immediate increase theviscosity of the slurry. The dispersed alumina was added to the slurry.The pH of the mixture was 6.9. The slurry was spray dried to produce aparticle of approximately 65 microns. The spray-dried product wascalcined in air for one hour at 1000° F. The calcined particles werethen tested for their resistance to attrition and found to have anAttrition Index of 1.5. The catalyst was also tested for activity aftersteam deactivation and found to have an Activity Index of 77.3.

Example 17

This example describes the preparation of a particle containing afaujasite zeolite catalyst formed into an attrition resistant materialusing a clay-phosphate binder. The faujasite zeolite is a rare earthexchanged Y-faujasite. The clay binder was prepared by diluting 1416grams of a 70% weight kaolin clay slurry with 585 milliliters of waterin a Waring blender. To the diluted clay 339 grams of a slurrycontaining 44% REY was added and mixed at high speed. To this slurry 114grams of 85% phosphoric acid was added. There was an immediate increasein the viscosity of the slurry. The pH of the resulting mixture was 4.0.The slurry was spray dried to produce a particle of approximately 65microns. The spray dried product was calcined in air for one hour at1000° F. The calcined particles were then tested for their resistance toattrition and found to have an Attrition Index of 1.1. The catalyst wasalso tested for activity after steam deactivation and found to have anActivity Index of 15.8.

Example 18

This example describes the preparation of a particle containing afaujasite zeolite catalyst formed into an attrition resistant materialusing a clay-phosphate binder. The faujasite zeolite is a ultra stableY-faujasite. The clay binder was prepared by diluting 852 grams of a 70%weight kaolin clay slurry with 1500 milliliters of water in a Waringblender. To the diluted clay 250 grams of ultra stable Y-faujasite wasadded and mixed at high speed. To this slurry 98 grams of 85% phosphoricacid was added. There was an immediate increase in the viscosity of theslurry. The pH of the resulting mixture was 3.0. The slurry was spraydried to produce a particle of approximately 65 microns. The spray driedproduct was calcined in air for one hour at 1000° F. The calcinedparticles were then tested for their resistance to attrition and foundto have an Attrition Index of 1.5. The catalyst was also tested foractivity after steam deactivation and found to have an Activity Index of68.2.

Example 19

This example describes the preparation of a particle containing afaujasite zeolite catalyst formed into an attrition resistant materialusing a conventional alumina gel binder. The faujasite component was amixture of a high rare earth exchanged Y-faujasite and a low rare earthexchanged Y-faujasite. The alumina gel was prepared by slurrying 167grams of Condea SB alumina in 1083 milliliters of water and peptizing itwith 34 milliliters of formic acid. The faujasite component whichtotaled 125 grams on a dry basis were slurried along with 294 grams ofclay in 600 milliliters of water. This slurry was mixed at high speed ina Waring blender; to this mixture the alumina gel was added. The slurrywas spray dried to produce a particle of approximately 65 microns. Thespray dried particles were calcined at 1350° F. The calcined particleswere then tested for their resistance to attrition and found to have anAttrition Index of 7.0. The catalyst was also tested for activity aftersteam deactivation and found to have an Activity index of 80.

Example 20

This example describes the preparation of a particle containing afaujasite zeolite catalyst formed into an attrition resistant materialusing a clay phosphate binder. The faujasite component was a mixture ofa high rare earth exchanged Y-faujasite and a low rare earthY-faujasite. The faujasite components which totaled 250 grams on a drybasis were slurried with 125 grams of Alcoa CP-1.5 activated alumina in1350 milliliters of water. To this slurry 980 grams of 60% weight clayslurry was added. The mixture was stirred at high speed in a Waringblender. A solution weighing 85.3 grams containing 25% weight dibasicammonium phosphate was added to the slurry. There was an immediateincrease in the viscosity of the slurry. The pH of the slurry was 8.2the slurry was spray dried to produce a particle of approximately 65microns. The spray dried particles were calcined at 1350° F. Thecalcined particles were then tested for their resistance to attritionand found to have an Attrition Index of 0.8. The catalyst was tested foractivity after steam deactivation and found to have an activity Index of85.

Finally, those skilled in this art also will appreciate that theconditions employed in the herein described processes will be thoseappropriate to the particular materials being used. As was previouslynoted, some variations may be introduced as a result of using clays fromdifferent mineral sources. In any case, while this invention generallyhas been described in terms of the general discussions, specificexamples and preferred embodiments, none of these should be takenindividually as a limit upon the overall inventive concepts describedherein.

Thus having disclosed this invention, what is claimed is:
 1. A processfor preparing attrition-resistant binder particles, said processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent clay; (2) adjusting the pH of the clay slurry to a levelwhich places an aluminum component of the clay in an oxidation statewhich is conducive to formation of an ammonium/aluminum/phosphatecomplex; (3) providing the clay slurry with ammonium ions and withphosphate ions by introducing therein an ammonium phosphate compoundselected from the group consisting of monoammonium acid orthophosphate,diammonium acid ortho phosphate and triammonium orthophosphate andthereby producing a clay slurry having ammonium aluminum phosphatecomplex units in a quantity such that the attrition-resistant binderparticles ultimately made from the slurry will be comprised of fromabout 1 to about 20 weight percent phosphate and from about 80 to about99 weight percent clay; (4) drying the slurry to produce solidparticles; and (5) calcining said solid particles in order to produceattrition-resistant binder particles.
 2. The process of claim 1 whereinthe phosphate ions are partially provided by introducing phosphoric acidinto the slurry.
 3. The process of claim 1 wherein the phosphate ionsare supplied by a mixture of monoammonium acid orthophosphate anddiammonium acid orthophosphate.
 4. The process of claim 1 wherein thephosphate ions are supplied by a mixture of phosphoric acid and anammonium phosphate compound selected from the group consisting ofmonoammonium acid orthophosphate, diammonium acid orthophosphate andtriammonium ortho phosphate.
 5. The process of claim 1 wherein anadditional ingredient comprising up to about 10 weight percent of theattrition-resistant binder particles is placed in the clay slurry inplace of a portion of a clay portion of said slurry.
 6. The process ofclaim 1 wherein the clay is kaolin clay.
 7. The process of claim 1 whichfurther comprises desiccating the particles resulting from the drying ata temperature higher than the boiling point of a liquid medium used tocreate the clay slurry for a period from about 0.2 hours to about 24.0hours in order to remove any residual amounts of the liquid medium andthereby obtaining, in the form of a powder, anhydrous particles.
 8. Theprocess of claim 1 wherein the calcining is carried out in a temperaturerange between about 1,000 degrees Fahrenheit and about 1,950 degreesFahrenheit for from about 60 minutes to about 240 minutes.
 9. Theprocess of claim 1 wherein additional amounts of a liquid medium areadded to a concentrated clay/water slurry in order to bring the slurry'sclay concentration to about 40 weight percent.
 10. The process of claim1 wherein the phosphate ions provide from about 6.0 to about 12.0 weightpercent of phosphate to the attrition-resistant binder material.
 11. Theprocess of claim 1 wherein the calcining is accomplished in a catalyticunit which employs the attrition-resistant binder particles.
 12. Aprocess for preparing attrition-resistant clay/phosphate/catalystparticles, said process comprising:(1) preparing a clay slurry havingfrom about 20 to about 50 weight percent clay; (2) adjusting the pH ofthe clay slurry to a level which places an aluminum component of theclay in an oxidation state which is conducive to formation of anammonium aluminum phosphate complex; (3) providing the clay slurry withammonium ions and with phosphate ions by introducing therein an ammoniumphosphate compound selected from the group consisting of monoammoniumacid orthophosphate, diammonium acid ortho phosphate and triammoniumorthophosphate and thereby producing a clay slurry having ammoniumaluminum phosphate complex units in a quantity such that theattrition-resistant binder particles ultimately made from the slurrywill be comprised of from about 1 to about 20 weight percent phosphateand from about 80 to about 99 weight percent clay; (4) mixing catalystparticles into the clay/phosphate-containing compound slurry to form aclay/phosphate-containing compound/catalyst particle slurry having aquantity of catalyst particles which is such that theattrition-resistant clay/phosphate/catalyst particles made from saidslurry will comprise from about 3 to about 60 weight percent of saidparticles; (5) drying the slurry to produce solid particles; and (6)calcining said solid particles in order to produce attrition-resistantclay/phosphate/catalyst particles.
 13. The process of claim 12 whereinthe phosphate ions are partially provided by introducing phosphoric acidinto the slurry.
 14. The process of claim 12 wherein the phosphate ionsare supplied by a mixture of monoammonium acid orthophosphate anddiammonium acid orthophosphate.
 15. The process of claim 12 wherein thephosphate ions are supplied by a mixture of phosphoric acid and anammonium phosphate compound selected from the group consisting ofmonoammonium acid orthophosphate, diammonium acid orthophosphate andtriammonium ortho phosphate.
 16. The process of claim 12 wherein anadditional ingredient comprising up to about 10 weight percent of theattrition-resistant binder particles is placed in the clay slurry inplace of a portion of a clay portion of said slurry.
 17. The process ofclaim 12 wherein the clay is kaolin clay.
 18. The process of claim 12which further comprises desiccating the particles resulting from thedrying at a temperature higher than the boiling point of a liquid mediumused to create the clay slurry for a period from about 0.2 hours toabout 24.0 hours in order to remove any residual amounts of the liquidmedium and thereby obtaining, in the form of a powder, anhydrousparticles.
 19. The process of claim 12 wherein the calcining is carriedout in a temperature range between about 1,000 degrees Fahrenheit andabout 1,950 degrees Fahrenheit for from about 60 minutes to about 240minutes.
 20. The process of claim 12 wherein additional amounts of aliquid medium are added to a concentrated clay/water slurry in order tobring the slurry's clay concentration to about 40 weight percent. 21.The process of claim 12 wherein the phosphate ions provide from about6.0 to about 12.0 weight percent of phosphate to the attrition-resistantbinder material.
 22. The process of claim 12 wherein the calcining isaccomplished in a catalytic unit which employs the attrition-resistantbinder particles.
 23. The process of claim 12 wherein the adjustment ofthe pH of the clay slurry also serves to produce a pH level whichpreserves catalytic activity of catalyst particles in theattrition-resistant clay/phosphate/catalyst particles.
 24. The processof claim 12 wherein the adjustment of the pH of the clay slurry isachieved through the use of a mixture of monoammonium acid orthophosphate and diammonium acid orthophosphate.
 25. The process of claim12 wherein the adjustment of the pH of the clay slurry is achievedthrough the use of a mixture of monoammonium acid ortho phosphate,diammonium acid orthophosphate and phosphoric acid.
 26. The process ofclaim 12 wherein the production of the ammonium aluminum phosphatecomplex units in the clay slurry is followed by a second pH adjustmentwhich produces a pH of from about 4.0 to about 8.0 and thereby preparesthe clay slurry to receive catalyst particles without causing diminishedcatalytic activity in said catalyst particles.
 27. A process forpreparing attrition-resistant binder particles, said processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent clay; (2) bringing the clay slurry to a pH of from about1.0 to about 3.0; (3) mixing a phosphate-containing compound into theclay slurry to form a clay/phosphate-containing compound slurry having aquantity of the phosphate-containing compound which is such that theattrition-resistant binder particles ultimately made from theclay/phosphate-containing compound slurry will be comprised of fromabout 2 to about 20 weight percent phosphate and from about 80 to about98 weight percent clay; (4) drying the clay/phosphate-containingcompound slurry to produce solid particles; and (5) calcining said solidparticles in order to produce attrition-resistant binder particles. 28.The process of claim 27 wherein the drying of the clay/phosphate slurryis accomplished by spray drying said slurry.
 29. The process of claim 27wherein the phosphate-containing compound is selected from the groupconsisting of a monobasic phosphate compound, a dibasic phosphatecompound or a tribasic phosphate compound.
 30. The process of claim 27wherein the phosphate-containing compound is selected from the groupconsisting of monobasic ammonium phosphate, dibasic ammonium phosphateand phosphoric acid.
 31. The process of claim 27 wherein thephosphate-containing compound is provided by a mixture of monobasicammonium phosphate and dibasic ammonium phosphate.
 32. The process ofclaim 27 wherein mixing the phosphate-containing compound into the clayslurry brings the clay slurry to a pH of from about 4.0 to about 8.0.33. The process of claim 27 wherein an additional ingredient comprisingup to about 10 weight percent of the attrition-resistant binderparticles is placed in the clay slurry in place of a portion of a clayportion of said slurry.
 34. The process of claim 27 wherein the clay iskaolin clay.
 35. The process of claim 27 which further comprisesdesiccating the particles resulting from the drying at a temperaturehigher than the boiling point of a liquid medium used to create the clayslurry for a period from about 0.2 hours to about 24.0 hours in order toremove any residual amounts of the liquid medium and thereby obtaining,in the form of a powder, anhydrous particles.
 36. The process of claim27 wherein the calcining is carried out in a temperature range betweenabout 1,000 degrees Fahrenheit and about 1,950 degrees Fahrenheit forfrom about 60 minutes to about 240 minutes.
 37. The process of claim 27wherein additional amounts of a liquid medium are added to aconcentrated clay/water slurry in order to bring the slurry's clayconcentration to about 40 weight percent.
 38. The process of claim 27wherein the quantity of phosphate-containing compound provides fromabout 6.0 to about 12.0 weight percent of phosphate to theattrition-resistant binder material.
 39. The process of claim 27 whereinthe calcining is accomplished in a catalytic unit which employs theattrition-resistant binder particles.
 40. A process for preparingattrition-resistant clay/phosphate/catalyst particles, said processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent of a clay; (2) bringing the clay slurry to a pH of fromabout 1.0 to about 3.0; (3) mixing a phosphate-containing compound intothe clay slurry to form a clay/phosphate-containing compound slurrywhich has sufficient phosphate to form a clay/phosphate-containingcompound slurry having a pH from about 4.0 to about 8.0 and provide aquantity of phosphate which is such that the clay/phosphate/catalystparticles ultimately made from said slurry will be comprised of fromabout 2 to about 20 weight percent phosphate; (4) mixing catalystparticles into the clay/phosphate-containing compound slurry to form aclay/phosphate-containing compound/catalyst particle slurry having aquantity of catalyst particles which is such that theattrition-resistant clay/phosphate/catalyst particles made from saidslurry will comprise from about 3 to about 60 weight percent of saidparticles; (5) drying said clay/phosphate-containing compound/catalystparticle slurry to produce solid particles; and (6) calcining said solidparticles to produce attrition-resistant clay/phosphate/catalystparticles which comprise from about 3 and about 60 weight percent of thecatalyst particles, from about 2 to about 20 weight percent of phosphateand from about 20 to about 95 weight percent clay.
 41. The process ofclaim 40 wherein the drying of the clay/phosphate-containing compoundslurry is accomplished by spray drying said slurry.
 42. The process ofclaim 40 wherein the phosphate-containing compound is selected from thegroup consisting of a monobasic phosphate compound, a dibasic phosphatecompound or a tribasic phosphate compound.
 43. The process of claim 40wherein the phosphate-containing compound is selected from the groupconsisting of monobasic ammonium phosphate, dibasic ammonium phosphateand phosphoric acid.
 44. The process of claim 40 wherein thephosphate-containing compound is provided by a mixture of monobasicammonium phosphate, dibasic ammonium phosphate and phosphoric acid. 45.The process of claim 40 wherein the bringing of the clay slurry to a pHof from 14.0 to about 10.0 is accomplished by introducing ammoniumhydroxide into the clay slurry.
 46. The process of claim 40 wherein anadditional ingredient comprising up to about 10 percent of theattrition-resistant binder particles is placed in the clay slurry inplace of a portion of a clay portion of said slurry.
 47. The process ofclaim 40 wherein the clay component is a kaolin clay.
 48. The process ofclaim 40 which further comprises desiccating the particles resultingfrom the spray drying at a temperature higher than the boiling point ofthe liquid medium for a period from about 0.2 hours to about 24.0 hoursin order to remove any residual amounts of the liquid medium and therebyobtaining, in the form of a powder, anhydrous particles.
 49. The processof claim 40 wherein the calcining is carried out in a temperature rangebetween about 1,000 degrees Fahrenheit and about 1,950 degreesFahrenheit for from about 60 minutes to about 240 minutes.
 50. Theprocess of claim 40 wherein the catalyst particles comprise about 25weight percent of the clay/phosphate/catalyst particles.
 51. The processof claim 40 wherein the quantity of phosphate compound provides fromabout 6.0 to about 12.0 weight percent of phosphate to theattrition-resistant binder material.
 52. The process of claim 40 whereina viscosity agent selected from the group consisting of starch and gumarabic is added to the slurry before it undergoes spray drying.
 53. Aprocess for preparing attrition-resistant clay/phosphate/catalystparticles, said process comprising:(1) preparing a clay slurry havingfrom about 20 to about 50 weight percent clay; (2) bringing the clayslurry to a pH of from about 14.0 to about 10.0; (3) mixing aphosphate-containing compound into the clay slurry to form aclay/phosphate-containing compound slurry having a quantity of phosphatewhich is such that the attrition-resistant binder particles ultimatelymade from the slurry will be comprised of from about 2 to about 20weight percent of phosphate and from about 80 to about 98 weight percentclay; (4) drying the clay/phosphate-containing slurry to produce solidparticles; (5) calcining said solid particles in order to produceattrition-resistant binder particles.
 54. The process of claim 53wherein the drying of the clay/phosphate/catalyst slurry is accomplishedby spray drying said slurry.
 55. The process of claim 53 wherein thephosphate-containing compound is selected from the group consisting of amonobasic phosphate compound, a dibasic phosphate compound or a tribasicphosphate compound.
 56. The process of claim 53 wherein thephosphate-containing compound is selected from the group consisting ofmonobasic ammonium phosphate, dibasic ammonium phosphate and phosphoricacid.
 57. The process of claim 53 wherein the phosphate-containingcompound is provided by a mixture of monobasic ammonium phosphate,dibasic ammonium phosphate and phosphoric acid.
 58. The process of claim53 wherein the bringing of the clay slurry to a pH of from 14.0 to about10.0 is accomplished by introducing ammonium hydroxide acid into saidclay slurry.
 59. The process of claim 53 wherein an additionalingredient comprising up to about 10 percent of the attrition-resistantbinder particles is placed in the clay slurry in place of a portion of aclay portion of said slurry.
 60. The process of claim 53 wherein theclay component is a kaolin clay.
 61. The process of claim 53 whichfurther comprises desiccating the particles resulting from the spraydrying at a temperature higher than the boiling point of the liquidmedium for a period from about 0.2 hours to about 24.0 hours in order toremove any residual amounts of the liquid medium and thereby obtaining,in the form of a powder, anhydrous particles.
 62. The process of claim53 wherein the mixing of the phosphate-containing compound into the clayslurry brings the clay slurry to a pH of from about 4.0 to about 8.0.63. The process of claim 53 wherein the calcining is accomplished in acatalytic unit which employs the attrition-resistant binder particles.64. The process of claim 53 wherein an additional ingredient comprisingup to about 10 percent of the attrition-resistant binder particles inplace of a portion of a clay portion of said slurry.
 65. The process ofclaim 53 wherein a viscosity agent selected from the group consisting ofstarch and gum arabic is added to the slurry before it undergoes spraydrying.
 66. A process for preparing attrition-resistantclay/phosphate/catalyst particles, said process comprising:(1) preparinga clay slurry having from about 20 to about 50 weight percent clay; (2)bringing the clay slurry to a pH of from about 14.0 to about 10.0; (3)mixing a phosphate-containing compound and an auxiliary binder material(which collectively constitute an auxiliary binder component of theattrition-resistant binder particles) into the clay slurry to form aclay/phosphate-containing compound/auxiliary binder material slurryhaving a quantity of auxiliary binder component which is such that theattrition-resistant binder particles ultimately made from theclay/phosphate-containing compound/auxiliary binder material slurry willbe comprised of from about 5.25 to about 60 weight percent of theauxiliary binder component and from about 40 to about 94.75 weightpercent of a clay component and wherein said auxiliary binder componentcontains an amount of phosphate which is sufficient to provide theattrition-resistant binder particles with at least about 0.25 weightpercent phosphate; (4) drying the clay/phosphate/auxiliary bindermaterial slurry to produce solid particles; and (5) calcining said solidparticles to produce attrition-resistant binder particles.
 67. Theprocess of claim 66 wherein the drying of the clay/phosphate slurry isaccomplished by spray drying said slurry.
 68. The process of claim 66wherein the phosphate-containing compound is selected from the groupconsisting of a monobasic phosphate compound, a dibasic phosphatecompound or a tribasic phosphate compound.
 69. The process of claim 66wherein the phosphate-containing compound is selected from the groupconsisting of monobasic ammonium phosphate, dibasic ammonium phosphateand phosphoric acid.
 70. The process of claim 66 wherein thephosphate-containing compound is provided by a mixture of monobasicammonium phosphate and dibasic ammonium phosphate.
 71. The process ofclaim 66 wherein the auxiliary binder material is selected from thegroup consisting of alumina, silica, alumino-silicate compounds,magnesia, silica-magnesia, chromia, zirconia, gallium and germanium. 72.The process of claim 66 wherein the bringing of the clay slurry to a pHof from 10.0 to about 14.0 is at least partially accomplished byintroducing ammonium hydroxide into the clay slurry.
 73. The process ofclaim 66 wherein the clay component is a kaolin clay.
 74. The process ofclaim 66 which further comprises desiccating the particles resultingfrom the spray drying at a temperature higher than the boiling point ofthe liquid medium for a period from about 0.2 hours to about 24.0 hoursin order to remove any residual amounts of the liquid medium and therebyobtaining, in the form of a powder, anhydrous particles the bindermaterial.
 75. The process of claim 66 wherein the calcining is carriedout in a temperature range between about 1,000 degrees Fahrenheit andabout 1,950 degrees Fahrenheit for from about 60 minutes to about 240minutes.
 76. The process of claim 66 wherein additional amounts of aliquid medium are added to a concentrated clay/water slurry in order tobring the slurry's clay concentration to about 40 weight percent. 77.The process of claim 66 wherein introduction of the phosphate-containingcompound brings the slurry to a pH of from about 4.0 to about 8.0. 78.The process of claim 66 wherein a viscosity agent selected from thegroup consisting of starch and gum arabic is added to the slurry beforeit undergoes spray drying.
 79. A process for preparingattrition-resistant binder particles, said process comprising:(1)preparing a clay slurry having from about 20 to about 50 weight percentof a clay ingredient; (2) bringing the clay slurry to a pH of from about14.0 to about 10.0; (3) mixing a phosphate-containing compound, anauxiliary binder material (which will collectively constitute anauxiliary binder component of the attrition-resistant binder particles)and an acid into the clay slurry which are collectively sufficient toform a clay/phosphate-containing compound/auxiliary binder material/acidslurry having a quantity of phosphate which is such that theattrition-resistant binder particles ultimately made from said slurrywill be comprised of from about 5.25 to about 40 weight percent of anauxiliary binder component and from about 40 to about 94.75 weightpercent clay and wherein said auxiliary binder component containssufficient phosphate to make the attrition-resistant binder particlescomprise at least about 0.25 weight percent phosphate; (4) drying theclay/phosphate-containing compound slurry to produce solid particles;and (5) calcining said solid particles to produce attrition-resistantbinder particles.
 80. The process of claim 79 wherein the drying of theclay/phosphate-containing compound/auxiliary binder component slurry isaccomplished by spray drying said slurry.
 81. The process of claim 79wherein the phosphate-containing compound is selected from the groupconsisting of a monobasic phosphate compound, a dibasic phosphatecompound or a tribasic phosphate compound.
 82. The process of claim 79wherein the phosphate-containing compound is selected from the groupconsisting of monobasic ammonium phosphate, dibasic ammonium phosphateand phosphoric acid.
 83. The process of claim 79 wherein thephosphate-containing compound is provided by a mixture of monobasicammonium phosphate and dibasic ammonium phosphate.
 84. The process ofclaim 79 wherein the bringing of the clay slurry to a pH of from 14.0 toabout 10.0 is accomplished by introducing phosphoric acid into the clayslurry.
 85. The process of claim 79 wherein the clay is a naturallyoccurring clay.
 86. The process of claim 79 wherein the clay componentis a kaolin clay.
 87. The process of claim 79 which further comprisesdesiccating the particles resulting from the spray drying at atemperature higher than the boiling point of the liquid medium for aperiod from about 0.2 hours to about 24.0 hours in order to remove anyresidual amounts of the liquid medium and thereby obtaining, in the formof a powder, anhydrous particles.
 88. The process of claim 79 whereinthe calcining is carried out in a temperature range between about 1,000degrees Fahrenheit and about 1,950 degrees Fahrenheit for from about 60minutes to about 240 minutes.
 89. The process of claim 79 whereinadditional amounts of a liquid medium are added to a concentratedclay/water slurry in order to bring the slurry's clay concentration toabout 40 weight percent.
 90. The process of claim 79 wherein a gasevolution agent is added to the total mixture before said mixtureundergoes spray drying.
 91. The process of claim 79 wherein a viscosityagent selected from the group consisting of starch and gum arabic isadded to the slurry before it undergoes spray drying.
 92. A process forpreparing attrition-resistant clay/phosphate/auxiliary bindermaterial/catalyst particles, said process comprising:(1) preparing aclay slurry having from about 20 to about 50 weight percent clay; (2)bringing the clay slurry to a pH of from about 10.0 to about 14.0; (3)mixing a phosphate-containing compound and an auxiliary binder material(which will collectively constitute an auxiliary binder component of theattrition-resistant clay/phosphate/auxiliary binder material/catalystmatrix particles) into the clay slurry in an amount which is such thatthe clay/phosphate/auxiliary binder material/ catalyst particlesproduced from said slurry will be comprised of from about 5.0 to about40 weight percent of the auxiliary binder component and wherein saidauxiliary binder component contains an amount of phosphate which issufficient to provide the attrition-resistant clay/phosphate/auxiliarybinder material/catalyst particles with at least about 0.25 weightpercent phosphate; (4) mixing a sufficient amount of catalyst particlesinto the clay/phosphate-containing/auxiliary binder material slurry toform a clay/phosphate-containing compound/auxiliary bindermaterial/catalyst particle slurry which has a quantity of catalystparticles which is such that the attrition-resistantclay/phosphate/auxiliary binder material/catalyst matrix particlesultimately made from this process will comprise from about 3 to about 60weight percent of said catalyst particles; (5) drying saidclay/phosphate compound/catalyst particle slurry to produce solidparticles; (6) calcining the solid particles to produceattrition-resistant clay/phosphate/auxiliary binder material/catalystparticles which comprise between about 3 and about 60 percent by weightof the catalyst particles, between about 20 and about 91.75 weightpercent clay and between about 5.25 and about 40 percent auxiliarybinder component and wherein said auxiliary binder component containssufficient phosphate-containing compound to make the attrition-resistantclay/phosphate/auxiliary binder material/catalyst particles comprise atleast about 0.25 weight percent phosphate.
 93. The process of claim 92wherein the drying of the clay/phosphate/auxiliary bindercomponent/catalyst slurry is accomplished by spray drying said slurry.94. The process of claim 92 wherein the phosphate-containing compound isselected from the group consisting of a monobasic phosphate compound, adibasic phosphate compound or a tribasic phosphate compound.
 95. Theprocess of claim 92 wherein the phosphate-containing compound isselected from the group consisting of monobasic ammonium phosphate,dibasic ammonium phosphate and phosphoric acid.
 96. The process of claim92 wherein the phosphate-containing compound is provided by a mixture ofmonobasic ammonium phosphate and dibasic ammonium phosphate.
 97. Theprocess of claim 92 wherein the bringing of the clay slurry to a pH offrom 10.0 to about 14.0 is at least partially accomplished byintroducing ammonium hydroxide into the clay slurry.
 98. The process ofclaim 92 wherein the attrition-resistant clay/phosphate/auxiliary bindermaterial/catalyst particles contain up to about 10 weight percent ofsome other ingredient.
 99. The process of claim 92 wherein the claycomponent is a kaolin clay.
 100. The process of claim 92 which furthercomprises desiccating the particles resulting from the spray drying at atemperature higher than the boiling point of the liquid medium for aperiod from about 0.2 hours to about 24.0 hours in order to remove anyresidual amounts of the liquid medium and thereby obtaining, in the formof a powder, anhydrous particles the binder material.
 101. The processof claim 92 wherein the calcining is carried out in a temperature rangebetween about 1,000 degrees Fahrenheit and about 1,950 degreesFahrenheit for from about 60 minutes to about 240 minutes.
 102. Theprocess of claim 92 wherein additional amounts of a liquid medium areadded to a concentrated clay/water slurry in order to bring the slurry'sclay concentration to about 40 weight percent.
 103. The process of claim92 wherein a gas evolution agent is added to the total mixture beforesaid mixture undergoes spray drying.
 104. The process of claim 92wherein a viscosity agent selected from the group consisting of starchand gum arabic is added to the slurry before it undergoes spray drying.105. Attrition-resistant binder particles, made by a processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent clay; (2) adjusting the pH of the clay slurry to a levelwhich places an aluminum component of the clay in an oxidation statewhich is conducive to formation of an ammonium/aluminum/phosphatecomplex; (3) providing the clay slurry with ammonium ions and withphosphate ions by introducing therein an ammonium phosphate compoundselected from the group consisting of monoammonium acid orthophosphate,diammonium acid ortho phosphate and triammonium orthophosphate andthereby producing a clay slurry having ammonium aluminum phosphatecomplex units in a quantity such that the attrition-resistant binderparticles ultimately made from the slurry will be comprised of fromabout 1 to about 20 weight percent phosphate and from about 80 to about99 weight percent clay; (4) drying the slurry to produce solidparticles; and (5) calcining said solid particles in order to produceattrition-resistant binder particles.
 106. Attrition-resistantclay/phosphate/catalyst particles, made by a process comprising:(1)preparing a clay slurry having from about 20 to about 50 weight percentclay; (2) adjusting the pH of the clay slurry to a level which places analuminum component of the clay in an oxidation state which is conduciveto formation of an ammonium aluminum phosphate complex; (3) providingthe clay slurry with ammonium ions and with phosphate ions byintroducing therein an ammonium phosphate compound selected from thegroup consisting of monoammonium acid orthophosphate, diammonium acidortho phosphate and triammonium orthophosphate and thereby producing aclay slurry having ammonium aluminum phosphate complex units in aquantity such that the attrition-resistant binder particles ultimatelymade from the slurry will be comprised of from about 1 to about 20weight percent phosphate and from about 80 to about 99 weight percentclay; (4) mixing catalyst particles into the clay/phosphate-containingcompound slurry to form a clay/phosphate-containing compound/catalystparticle slurry having a quantity of catalyst particles which is suchthat the attrition-resistant clay/phosphate/catalyst particles made fromsaid slurry will comprise from about 3 to about 60 weight percent ofsaid particles; (5) drying the slurry to produce solid particles; and(6) calcining said solid particles in order to produceattrition-resistant clay/phosphate/catalyst particles. 107.Attrition-resistant binder particles, made by a process comprising:(1)preparing a clay slurry having from about 20 to about 50 weight percentclay; (2) bringing the clay slurry to a pH of from about 1.0 to about3.0; (3) mixing a phosphate-containing compound into the clay slurry toform a clay/phosphate-containing compound slurry having a quantity ofthe phosphate-containing compound which is such that theattrition-resistant binder particles ultimately made from theclay/phosphate-containing compound slurry will be comprised of fromabout 2 to about 20 weight percent phosphate and from about 80 to about98 weight percent clay; (4) drying the clay/phosphate-containingcompound slurry to produce solid particles; and (5) calcining said solidparticles in order to produce attrition-resistant binder particles. 108.Attrition-resistant clay/phosphate/catalyst particles, made by a processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent of a clay; (2) bringing the clay slurry to a pH of fromabout 1.0 to about 3.0; (3) mixing a phosphate-containing compound intothe clay slurry to form a clay/phosphate-containing compound slurrywhich has sufficient phosphate to form a clay/phosphate-containingcompound slurry having a pH from about 4.0 to about 8.0 and provide aquantity of phosphate which is such that the clay/phosphate/catalystparticles ultimately made from said slurry will be comprised of fromabout 2 to about 20 weight percent phosphate; (4) mixing catalystparticles into the clay/phosphate-containing compound slurry to form aclay/phosphate-containing compound/catalyst particle slurry having aquantity of catalyst particles which is such that theattrition-resistant clay/phosphate/catalyst particles made from saidslurry will comprise from about 3 to about 60 weight percent of saidparticles; (5) drying said clay/phosphate-containing compound/catalystparticle slurry to produce solid particles; and (6) calcining said solidparticles to produce attrition-resistant clay/phosphate/catalystparticles which comprise from about 3 and about 60 weight percent of thecatalyst particles, from about 2 to about 20 weight percent of phosphateand from about 20 to about 95 weight percent clay. 109.Attrition-resistant clay/phosphate/catalyst particles, made by a processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent clay; (2) bringing the clay slurry to a pH of from about14.0 to about 10.0; (3) mixing a phosphate-containing compound into theclay slurry to form a clay/phosphate-containing compound slurry having aquantity of phosphate which is such that the attrition-resistant binderparticles ultimately made from the slurry will be comprised of fromabout 2 to about 20 weight percent of phosphate and from about 80 toabout 98 weight percent clay; (4) drying the clay/phosphate-containingslurry to produce solid particles; (5) calcining said solid particles inorder to produce attrition-resistant binder particles. 110.Attrition-resistant clay/phosphate/catalyst particles, made by a processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent clay; (2) bringing the clay slurry to a pH of from about14.0 to about 10.0; (3) mixing a phosphate-containing compound and anauxiliary binder material (which collectively constitute an auxiliarybinder component of the attrition-resistant binder particles) into theclay slurry to form a clay/phosphate-containing compound/auxiliarybinder material slurry having a quantity of auxiliary binder componentwhich is such that the attrition-resistant binder particles ultimatelymade from the clay/phosphate-containing compound/auxiliary bindermaterial slurry will be comprised of from about 5.25 to about 60 weightpercent of the auxiliary binder component and from about 40 to about94.75 weight percent of a clay component and wherein said auxiliarybinder component contains an amount of phosphate which is sufficient toprovide the attrition-resistant binder particles with at least about0.25 weight percent phosphate; (4) drying the clay/phosphate/auxiliarybinder material slurry to produce solid particles; and (5) calciningsaid solid particles to produce attrition-resistant binder particles.111. Attrition-resistant binder particles, made by a processcomprising:(1) preparing a clay slurry having from about 20 to about 50weight percent of a clay ingredient; (2) bringing the clay slurry to apH of from about 14.0 to about 10.0; (3) mixing a phosphate-containingcompound, an auxiliary binder material (which will collectivelyconstitute an auxiliary binder component of the attrition-resistantbinder particles) and an acid into the clay slurry which arecollectively sufficient to form a clay/phosphate-containingcompound/auxiliary binder material/acid slurry having a quantity ofphosphate which is such that the attrition-resistant binder particlesultimately made from said slurry will be comprised of from about 5.25 toabout 40 weight percent of an auxiliary binder component and from about40 to about 94.75 weight percent clay and wherein said auxiliary bindercomponent contains sufficient phosphate to make the attrition-resistantbinder particles comprise at least about 0.25 weight percent phosphate;(4) drying the clay/phosphate-containing compound slurry to producesolid particles; and (5) calcining said solid particles to produceattrition-resistant binder particles. 112.Attrition-resistantclay/phosphate/auxiliary binder material/catalystparticles, made by a process comprising:(1) preparing a clay slurryhaving from about 20 to about 50 weight percent clay; (2) bringing theclay slurry to a pH of from about 10.0 to about 14.0; (3) mixing aphosphate-containing compound and an auxiliary binder material (whichwill collectively constitute an auxiliary binder component of theattrition-resistant clay/phosphate/auxiliary binder material/catalystmatrix particles) into the clay slurry in an amount which is such thatthe clay/phosphate/auxiliary binder material/ catalyst particlesproduced from said slurry will be comprised of from about 5.0 to about40 weight percent of the auxiliary binder component and wherein saidauxiliary binder component contains an amount of phosphate which issufficient to provide the attrition-resistant clay/phosphate/auxiliarybinder material/catalyst particles with at least about 0.25 weightpercent phosphate; (4) mixing a sufficient amount of catalyst particlesinto the clay/phosphate-containing/auxiliary binder material slurry toform a clay/phosphate-containing compound/auxiliary bindermaterial/catalyst particle slurry which has a quantity of catalystparticles which is such that the attrition-resistantclay/phosphate/auxiliary binder material/catalyst matrix particlesultimately made from this process will comprise from about 3 to about 60weight percent of said catalyst particles; (5) drying saidclay/phosphate compound/catalyst particle slurry to produce solidparticles; (6) calcining the solid particles to produceattrition-resistant clay/phosphate/auxiliary binder material/catalystparticles which comprise between about 3 and about 60 percent by weightof the catalyst particles, between about 20 and about 91.75 weightpercent clay and between about 5.25 and about 40 percent auxiliarybinder component and wherein said auxiliary binder component containssufficient phosphate-containing compound to make the attrition-resistantclay/phosphate/auxiliary binder material/catalyst particles comprise atleast about 0.25 weight percent phosphate.